// Kludges for bugs and behavior differences that can't be feature
// detected are enabled based on userAgent etc sniffing.
var userAgent = navigator.userAgent;
var platform = navigator.platform;

var gecko = /gecko\/\d/i.test(userAgent);
var ie_upto10 = /MSIE \d/.test(userAgent);
var ie_11up = /Trident\/(?:[7-9]|\d{2,})\..*rv:(\d+)/.exec(userAgent);
var edge = /Edge\/(\d+)/.exec(userAgent);
var ie = ie_upto10 || ie_11up || edge;
var ie_version = ie && (ie_upto10 ? document.documentMode || 6 : +(edge || ie_11up)[1]);
var webkit = !edge && /WebKit\//.test(userAgent);
var qtwebkit = webkit && /Qt\/\d+\.\d+/.test(userAgent);
var chrome = !edge && /Chrome\//.test(userAgent);
var presto = /Opera\//.test(userAgent);
var safari = /Apple Computer/.test(navigator.vendor);
var mac_geMountainLion = /Mac OS X 1\d\D([8-9]|\d\d)\D/.test(userAgent);
var phantom = /PhantomJS/.test(userAgent);

var ios = !edge && /AppleWebKit/.test(userAgent) && /Mobile\/\w+/.test(userAgent);
var android = /Android/.test(userAgent);
// This is woefully incomplete. Suggestions for alternative methods welcome.
var mobile = ios || android || /webOS|BlackBerry|Opera Mini|Opera Mobi|IEMobile/i.test(userAgent);
var mac = ios || /Mac/.test(platform);
var chromeOS = /\bCrOS\b/.test(userAgent);
var windows = /win/i.test(platform);

var presto_version = presto && userAgent.match(/Version\/(\d*\.\d*)/);
if (presto_version) {
    presto_version = Number(presto_version[1]);
}
if (presto_version && presto_version >= 15) {
    presto = false;
    webkit = true;
}
// Some browsers use the wrong event properties to signal cmd/ctrl on OS X
var flipCtrlCmd = mac && (qtwebkit || presto && (presto_version == null || presto_version < 12.11));
var captureRightClick = gecko || (ie && ie_version >= 9);

function classTest(cls) {
    return new RegExp("(^|\\s)" + cls + "(?:$|\\s)\\s*")
}

var rmClass = function (node, cls) {
    var current = node.className;
    var match = classTest(cls).exec(current);
    if (match) {
        var after = current.slice(match.index + match[0].length);
        node.className = current.slice(0, match.index) + (after ? match[1] + after : "");
    }
};

function removeChildren(e) {
    for (var count = e.childNodes.length; count > 0; --count) {
        e.removeChild(e.firstChild);
    }
    return e
}

function removeChildrenAndAdd(parent, e) {
    return removeChildren(parent).appendChild(e)
}

function elt(tag, content, className, style) {
    var e = document.createElement(tag);
    if (className) {
        e.className = className;
    }
    if (style) {
        e.style.cssText = style;
    }
    if (typeof content == "string") {
        e.appendChild(document.createTextNode(content));
    } else if (content) {
        for (var i = 0; i < content.length; ++i) {
            e.appendChild(content[i]);
        }
    }
    return e
}

// wrapper for elt, which removes the elt from the accessibility tree
function eltP(tag, content, className, style) {
    var e = elt(tag, content, className, style);
    e.setAttribute("role", "presentation");
    return e
}

var range;
if (document.createRange) {
    range = function (node, start, end, endNode) {
        var r = document.createRange();
        r.setEnd(endNode || node, end);
        r.setStart(node, start);
        return r
    };
} else {
    range = function (node, start, end) {
        var r = document.body.createTextRange();
        try {
            r.moveToElementText(node.parentNode);
        } catch (e) {
            return r
        }
        r.collapse(true);
        r.moveEnd("character", end);
        r.moveStart("character", start);
        return r
    };
}

function contains(parent, child) {
    if (child.nodeType == 3) // Android browser always returns false when child is a textnode
    {
        child = child.parentNode;
    }
    if (parent.contains) {
        return parent.contains(child)
    }
    do {
        if (child.nodeType == 11) {
            child = child.host;
        }
        if (child == parent) {
            return true
        }
    } while (child = child.parentNode)
}

function activeElt() {
    // IE and Edge may throw an "Unspecified Error" when accessing document.activeElement.
    // IE < 10 will throw when accessed while the page is loading or in an iframe.
    // IE > 9 and Edge will throw when accessed in an iframe if document.body is unavailable.
    var activeElement;
    try {
        activeElement = document.activeElement;
    } catch (e) {
        activeElement = document.body || null;
    }
    while (activeElement && activeElement.shadowRoot && activeElement.shadowRoot.activeElement) {
        activeElement = activeElement.shadowRoot.activeElement;
    }
    return activeElement
}

function addClass(node, cls) {
    var current = node.className;
    if (!classTest(cls).test(current)) {
        node.className += (current ? " " : "") + cls;
    }
}

function joinClasses(a, b) {
    var as = a.split(" ");
    for (var i = 0; i < as.length; i++) {
        if (as[i] && !classTest(as[i]).test(b)) {
            b += " " + as[i];
        }
    }
    return b
}

var selectInput = function (node) {
    node.select();
};
if (ios) // Mobile Safari apparently has a bug where select() is broken.
{
    selectInput = function (node) {
        node.selectionStart = 0;
        node.selectionEnd = node.value.length;
    };
} else if (ie) // Suppress mysterious IE10 errors
{
    selectInput = function (node) {
        try {
            node.select();
        } catch (_e) {
        }
    };
}

function bind(f) {
    var args = Array.prototype.slice.call(arguments, 1);
    return function () {
        return f.apply(null, args)
    }
}

function copyObj(obj, target, overwrite) {
    if (!target) {
        target = {};
    }
    for (var prop in obj) {
        if (obj.hasOwnProperty(prop) && (overwrite !== false || !target.hasOwnProperty(prop))) {
            target[prop] = obj[prop];
        }
    }
    return target
}

// Counts the column offset in a string, taking tabs into account.
// Used mostly to find indentation.
function countColumn(string, end, tabSize, startIndex, startValue) {
    if (end == null) {
        end = string.search(/[^\s\u00a0]/);
        if (end == -1) {
            end = string.length;
        }
    }
    for (var i = startIndex || 0, n = startValue || 0; ;) {
        var nextTab = string.indexOf("\t", i);
        if (nextTab < 0 || nextTab >= end) {
            return n + (end - i)
        }
        n += nextTab - i;
        n += tabSize - (n % tabSize);
        i = nextTab + 1;
    }
}

var Delayed = function () {
    this.id = null;
    this.f = null;
    this.time = 0;
    this.handler = bind(this.onTimeout, this);
};
Delayed.prototype.onTimeout = function (self) {
    self.id = 0;
    if (self.time <= +new Date) {
        self.f();
    } else {
        setTimeout(self.handler, self.time - +new Date);
    }
};
Delayed.prototype.set = function (ms, f) {
    this.f = f;
    var time = +new Date + ms;
    if (!this.id || time < this.time) {
        clearTimeout(this.id);
        this.id = setTimeout(this.handler, ms);
        this.time = time;
    }
};

function indexOf(array, elt) {
    for (var i = 0; i < array.length; ++i) {
        if (array[i] == elt) {
            return i
        }
    }
    return -1
}

// Number of pixels added to scroller and sizer to hide scrollbar
var scrollerGap = 30;

// Returned or thrown by various protocols to signal 'I'm not
// handling this'.
var Pass = {
    toString: function () {
        return "CodeMirror.Pass"
    }
};

// Reused option objects for setSelection & friends
var sel_dontScroll = {scroll: false}, sel_mouse = {origin: "*mouse"}, sel_move = {origin: "+move"};

// The inverse of countColumn -- find the offset that corresponds to
// a particular column.
function findColumn(string, goal, tabSize) {
    for (var pos = 0, col = 0; ;) {
        var nextTab = string.indexOf("\t", pos);
        if (nextTab == -1) {
            nextTab = string.length;
        }
        var skipped = nextTab - pos;
        if (nextTab == string.length || col + skipped >= goal) {
            return pos + Math.min(skipped, goal - col)
        }
        col += nextTab - pos;
        col += tabSize - (col % tabSize);
        pos = nextTab + 1;
        if (col >= goal) {
            return pos
        }
    }
}

var spaceStrs = [""];

function spaceStr(n) {
    while (spaceStrs.length <= n) {
        spaceStrs.push(lst(spaceStrs) + " ");
    }
    return spaceStrs[n]
}

function lst(arr) {
    return arr[arr.length - 1]
}

function map(array, f) {
    var out = [];
    for (var i = 0; i < array.length; i++) {
        out[i] = f(array[i], i);
    }
    return out
}

function insertSorted(array, value, score) {
    var pos = 0, priority = score(value);
    while (pos < array.length && score(array[pos]) <= priority) {
        pos++;
    }
    array.splice(pos, 0, value);
}

function nothing() {
}

function createObj(base, props) {
    var inst;
    if (Object.create) {
        inst = Object.create(base);
    } else {
        nothing.prototype = base;
        inst = new nothing();
    }
    if (props) {
        copyObj(props, inst);
    }
    return inst
}

var nonASCIISingleCaseWordChar = /[\u00df\u0587\u0590-\u05f4\u0600-\u06ff\u3040-\u309f\u30a0-\u30ff\u3400-\u4db5\u4e00-\u9fcc\uac00-\ud7af]/;

function isWordCharBasic(ch) {
    return /\w/.test(ch) || ch > "\x80" &&
        (ch.toUpperCase() != ch.toLowerCase() || nonASCIISingleCaseWordChar.test(ch))
}

function isWordChar(ch, helper) {
    if (!helper) {
        return isWordCharBasic(ch)
    }
    if (helper.source.indexOf("\\w") > -1 && isWordCharBasic(ch)) {
        return true
    }
    return helper.test(ch)
}

function isEmpty(obj) {
    for (var n in obj) {
        if (obj.hasOwnProperty(n) && obj[n]) {
            return false
        }
    }
    return true
}

// Extending unicode characters. A series of a non-extending char +
// any number of extending chars is treated as a single unit as far
// as editing and measuring is concerned. This is not fully correct,
// since some scripts/fonts/browsers also treat other configurations
// of code points as a group.
var extendingChars = /[\u0300-\u036f\u0483-\u0489\u0591-\u05bd\u05bf\u05c1\u05c2\u05c4\u05c5\u05c7\u0610-\u061a\u064b-\u065e\u0670\u06d6-\u06dc\u06de-\u06e4\u06e7\u06e8\u06ea-\u06ed\u0711\u0730-\u074a\u07a6-\u07b0\u07eb-\u07f3\u0816-\u0819\u081b-\u0823\u0825-\u0827\u0829-\u082d\u0900-\u0902\u093c\u0941-\u0948\u094d\u0951-\u0955\u0962\u0963\u0981\u09bc\u09be\u09c1-\u09c4\u09cd\u09d7\u09e2\u09e3\u0a01\u0a02\u0a3c\u0a41\u0a42\u0a47\u0a48\u0a4b-\u0a4d\u0a51\u0a70\u0a71\u0a75\u0a81\u0a82\u0abc\u0ac1-\u0ac5\u0ac7\u0ac8\u0acd\u0ae2\u0ae3\u0b01\u0b3c\u0b3e\u0b3f\u0b41-\u0b44\u0b4d\u0b56\u0b57\u0b62\u0b63\u0b82\u0bbe\u0bc0\u0bcd\u0bd7\u0c3e-\u0c40\u0c46-\u0c48\u0c4a-\u0c4d\u0c55\u0c56\u0c62\u0c63\u0cbc\u0cbf\u0cc2\u0cc6\u0ccc\u0ccd\u0cd5\u0cd6\u0ce2\u0ce3\u0d3e\u0d41-\u0d44\u0d4d\u0d57\u0d62\u0d63\u0dca\u0dcf\u0dd2-\u0dd4\u0dd6\u0ddf\u0e31\u0e34-\u0e3a\u0e47-\u0e4e\u0eb1\u0eb4-\u0eb9\u0ebb\u0ebc\u0ec8-\u0ecd\u0f18\u0f19\u0f35\u0f37\u0f39\u0f71-\u0f7e\u0f80-\u0f84\u0f86\u0f87\u0f90-\u0f97\u0f99-\u0fbc\u0fc6\u102d-\u1030\u1032-\u1037\u1039\u103a\u103d\u103e\u1058\u1059\u105e-\u1060\u1071-\u1074\u1082\u1085\u1086\u108d\u109d\u135f\u1712-\u1714\u1732-\u1734\u1752\u1753\u1772\u1773\u17b7-\u17bd\u17c6\u17c9-\u17d3\u17dd\u180b-\u180d\u18a9\u1920-\u1922\u1927\u1928\u1932\u1939-\u193b\u1a17\u1a18\u1a56\u1a58-\u1a5e\u1a60\u1a62\u1a65-\u1a6c\u1a73-\u1a7c\u1a7f\u1b00-\u1b03\u1b34\u1b36-\u1b3a\u1b3c\u1b42\u1b6b-\u1b73\u1b80\u1b81\u1ba2-\u1ba5\u1ba8\u1ba9\u1c2c-\u1c33\u1c36\u1c37\u1cd0-\u1cd2\u1cd4-\u1ce0\u1ce2-\u1ce8\u1ced\u1dc0-\u1de6\u1dfd-\u1dff\u200c\u200d\u20d0-\u20f0\u2cef-\u2cf1\u2de0-\u2dff\u302a-\u302f\u3099\u309a\ua66f-\ua672\ua67c\ua67d\ua6f0\ua6f1\ua802\ua806\ua80b\ua825\ua826\ua8c4\ua8e0-\ua8f1\ua926-\ua92d\ua947-\ua951\ua980-\ua982\ua9b3\ua9b6-\ua9b9\ua9bc\uaa29-\uaa2e\uaa31\uaa32\uaa35\uaa36\uaa43\uaa4c\uaab0\uaab2-\uaab4\uaab7\uaab8\uaabe\uaabf\uaac1\uabe5\uabe8\uabed\udc00-\udfff\ufb1e\ufe00-\ufe0f\ufe20-\ufe26\uff9e\uff9f]/;

function isExtendingChar(ch) {
    return ch.charCodeAt(0) >= 768 && extendingChars.test(ch)
}

// Returns a number from the range [`0`; `str.length`] unless `pos` is outside that range.
function skipExtendingChars(str, pos, dir) {
    while ((dir < 0 ? pos > 0 : pos < str.length) && isExtendingChar(str.charAt(pos))) {
        pos += dir;
    }
    return pos
}

// Returns the value from the range [`from`; `to`] that satisfies
// `pred` and is closest to `from`. Assumes that at least `to`
// satisfies `pred`. Supports `from` being greater than `to`.
function findFirst(pred, from, to) {
    // At any point we are certain `to` satisfies `pred`, don't know
    // whether `from` does.
    var dir = from > to ? -1 : 1;
    for (; ;) {
        if (from == to) {
            return from
        }
        var midF = (from + to) / 2, mid = dir < 0 ? Math.ceil(midF) : Math.floor(midF);
        if (mid == from) {
            return pred(mid) ? from : to
        }
        if (pred(mid)) {
            to = mid;
        } else {
            from = mid + dir;
        }
    }
}

// BIDI HELPERS

function iterateBidiSections(order, from, to, f) {
    if (!order) {
        return f(from, to, "ltr", 0)
    }
    var found = false;
    for (var i = 0; i < order.length; ++i) {
        var part = order[i];
        if (part.from < to && part.to > from || from == to && part.to == from) {
            f(Math.max(part.from, from), Math.min(part.to, to), part.level == 1 ? "rtl" : "ltr", i);
            found = true;
        }
    }
    if (!found) {
        f(from, to, "ltr");
    }
}

var bidiOther = null;

function getBidiPartAt(order, ch, sticky) {
    var found;
    bidiOther = null;
    for (var i = 0; i < order.length; ++i) {
        var cur = order[i];
        if (cur.from < ch && cur.to > ch) {
            return i
        }
        if (cur.to == ch) {
            if (cur.from != cur.to && sticky == "before") {
                found = i;
            } else {
                bidiOther = i;
            }
        }
        if (cur.from == ch) {
            if (cur.from != cur.to && sticky != "before") {
                found = i;
            } else {
                bidiOther = i;
            }
        }
    }
    return found != null ? found : bidiOther
}

// Bidirectional ordering algorithm
// See http://unicode.org/reports/tr9/tr9-13.html for the algorithm
// that this (partially) implements.

// One-char codes used for character types:
// L (L):   Left-to-Right
// R (R):   Right-to-Left
// r (AL):  Right-to-Left Arabic
// 1 (EN):  European Number
// + (ES):  European Number Separator
// % (ET):  European Number Terminator
// n (AN):  Arabic Number
// , (CS):  Common Number Separator
// m (NSM): Non-Spacing Mark
// b (BN):  Boundary Neutral
// s (B):   Paragraph Separator
// t (S):   Segment Separator
// w (WS):  Whitespace
// N (ON):  Other Neutrals

// Returns null if characters are ordered as they appear
// (left-to-right), or an array of sections ({from, to, level}
// objects) in the order in which they occur visually.
var bidiOrdering = (function () {
    // Character types for codepoints 0 to 0xff
    var lowTypes = "bbbbbbbbbtstwsbbbbbbbbbbbbbbssstwNN%%%NNNNNN,N,N1111111111NNNNNNNLLLLLLLLLLLLLLLLLLLLLLLLLLNNNNNNLLLLLLLLLLLLLLLLLLLLLLLLLLNNNNbbbbbbsbbbbbbbbbbbbbbbbbbbbbbbbbb,N%%%%NNNNLNNNNN%%11NLNNN1LNNNNNLLLLLLLLLLLLLLLLLLLLLLLNLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLN";
    // Character types for codepoints 0x600 to 0x6f9
    var arabicTypes = "nnnnnnNNr%%r,rNNmmmmmmmmmmmrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrmmmmmmmmmmmmmmmmmmmmmnnnnnnnnnn%nnrrrmrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrmmmmmmmnNmmmmmmrrmmNmmmmrr1111111111";

    function charType(code) {
        if (code <= 0xf7) {
            return lowTypes.charAt(code)
        } else if (0x590 <= code && code <= 0x5f4) {
            return "R"
        } else if (0x600 <= code && code <= 0x6f9) {
            return arabicTypes.charAt(code - 0x600)
        } else if (0x6ee <= code && code <= 0x8ac) {
            return "r"
        } else if (0x2000 <= code && code <= 0x200b) {
            return "w"
        } else if (code == 0x200c) {
            return "b"
        } else {
            return "L"
        }
    }

    var bidiRE = /[\u0590-\u05f4\u0600-\u06ff\u0700-\u08ac]/;
    var isNeutral = /[stwN]/, isStrong = /[LRr]/, countsAsLeft = /[Lb1n]/, countsAsNum = /[1n]/;

    function BidiSpan(level, from, to) {
        this.level = level;
        this.from = from;
        this.to = to;
    }

    return function (str, direction) {
        var outerType = direction == "ltr" ? "L" : "R";

        if (str.length == 0 || direction == "ltr" && !bidiRE.test(str)) {
            return false
        }
        var len = str.length, types = [];
        for (var i = 0; i < len; ++i) {
            types.push(charType(str.charCodeAt(i)));
        }

        // W1. Examine each non-spacing mark (NSM) in the level run, and
        // change the type of the NSM to the type of the previous
        // character. If the NSM is at the start of the level run, it will
        // get the type of sor.
        for (var i$1 = 0, prev = outerType; i$1 < len; ++i$1) {
            var type = types[i$1];
            if (type == "m") {
                types[i$1] = prev;
            } else {
                prev = type;
            }
        }

        // W2. Search backwards from each instance of a European number
        // until the first strong type (R, L, AL, or sor) is found. If an
        // AL is found, change the type of the European number to Arabic
        // number.
        // W3. Change all ALs to R.
        for (var i$2 = 0, cur = outerType; i$2 < len; ++i$2) {
            var type$1 = types[i$2];
            if (type$1 == "1" && cur == "r") {
                types[i$2] = "n";
            } else if (isStrong.test(type$1)) {
                cur = type$1;
                if (type$1 == "r") {
                    types[i$2] = "R";
                }
            }
        }

        // W4. A single European separator between two European numbers
        // changes to a European number. A single common separator between
        // two numbers of the same type changes to that type.
        for (var i$3 = 1, prev$1 = types[0]; i$3 < len - 1; ++i$3) {
            var type$2 = types[i$3];
            if (type$2 == "+" && prev$1 == "1" && types[i$3 + 1] == "1") {
                types[i$3] = "1";
            } else if (type$2 == "," && prev$1 == types[i$3 + 1] &&
                (prev$1 == "1" || prev$1 == "n")) {
                types[i$3] = prev$1;
            }
            prev$1 = type$2;
        }

        // W5. A sequence of European terminators adjacent to European
        // numbers changes to all European numbers.
        // W6. Otherwise, separators and terminators change to Other
        // Neutral.
        for (var i$4 = 0; i$4 < len; ++i$4) {
            var type$3 = types[i$4];
            if (type$3 == ",") {
                types[i$4] = "N";
            } else if (type$3 == "%") {
                var end = (void 0);
                for (end = i$4 + 1; end < len && types[end] == "%"; ++end) {
                }
                var replace = (i$4 && types[i$4 - 1] == "!") || (end < len && types[end] == "1") ? "1" : "N";
                for (var j = i$4; j < end; ++j) {
                    types[j] = replace;
                }
                i$4 = end - 1;
            }
        }

        // W7. Search backwards from each instance of a European number
        // until the first strong type (R, L, or sor) is found. If an L is
        // found, then change the type of the European number to L.
        for (var i$5 = 0, cur$1 = outerType; i$5 < len; ++i$5) {
            var type$4 = types[i$5];
            if (cur$1 == "L" && type$4 == "1") {
                types[i$5] = "L";
            } else if (isStrong.test(type$4)) {
                cur$1 = type$4;
            }
        }

        // N1. A sequence of neutrals takes the direction of the
        // surrounding strong text if the text on both sides has the same
        // direction. European and Arabic numbers act as if they were R in
        // terms of their influence on neutrals. Start-of-level-run (sor)
        // and end-of-level-run (eor) are used at level run boundaries.
        // N2. Any remaining neutrals take the embedding direction.
        for (var i$6 = 0; i$6 < len; ++i$6) {
            if (isNeutral.test(types[i$6])) {
                var end$1 = (void 0);
                for (end$1 = i$6 + 1; end$1 < len && isNeutral.test(types[end$1]); ++end$1) {
                }
                var before = (i$6 ? types[i$6 - 1] : outerType) == "L";
                var after = (end$1 < len ? types[end$1] : outerType) == "L";
                var replace$1 = before == after ? (before ? "L" : "R") : outerType;
                for (var j$1 = i$6; j$1 < end$1; ++j$1) {
                    types[j$1] = replace$1;
                }
                i$6 = end$1 - 1;
            }
        }

        // Here we depart from the documented algorithm, in order to avoid
        // building up an actual levels array. Since there are only three
        // levels (0, 1, 2) in an implementation that doesn't take
        // explicit embedding into account, we can build up the order on
        // the fly, without following the level-based algorithm.
        var order = [], m;
        for (var i$7 = 0; i$7 < len;) {
            if (countsAsLeft.test(types[i$7])) {
                var start = i$7;
                for (++i$7; i$7 < len && countsAsLeft.test(types[i$7]); ++i$7) {
                }
                order.push(new BidiSpan(0, start, i$7));
            } else {
                var pos = i$7, at = order.length;
                for (++i$7; i$7 < len && types[i$7] != "L"; ++i$7) {
                }
                for (var j$2 = pos; j$2 < i$7;) {
                    if (countsAsNum.test(types[j$2])) {
                        if (pos < j$2) {
                            order.splice(at, 0, new BidiSpan(1, pos, j$2));
                        }
                        var nstart = j$2;
                        for (++j$2; j$2 < i$7 && countsAsNum.test(types[j$2]); ++j$2) {
                        }
                        order.splice(at, 0, new BidiSpan(2, nstart, j$2));
                        pos = j$2;
                    } else {
                        ++j$2;
                    }
                }
                if (pos < i$7) {
                    order.splice(at, 0, new BidiSpan(1, pos, i$7));
                }
            }
        }
        if (direction == "ltr") {
            if (order[0].level == 1 && (m = str.match(/^\s+/))) {
                order[0].from = m[0].length;
                order.unshift(new BidiSpan(0, 0, m[0].length));
            }
            if (lst(order).level == 1 && (m = str.match(/\s+$/))) {
                lst(order).to -= m[0].length;
                order.push(new BidiSpan(0, len - m[0].length, len));
            }
        }

        return direction == "rtl" ? order.reverse() : order
    }
})();

// Get the bidi ordering for the given line (and cache it). Returns
// false for lines that are fully left-to-right, and an array of
// BidiSpan objects otherwise.
function getOrder(line, direction) {
    var order = line.order;
    if (order == null) {
        order = line.order = bidiOrdering(line.text, direction);
    }
    return order
}
var noHandlers = [];

var on = function (emitter, type, f) {
    if (emitter.addEventListener) {
        emitter.addEventListener(type, f, false);
    } else if (emitter.attachEvent) {
        emitter.attachEvent("on" + type, f);
    } else {
        var map$$1 = emitter._handlers || (emitter._handlers = {});
        map$$1[type] = (map$$1[type] || noHandlers).concat(f);
    }
};

function getHandlers(emitter, type) {
    return emitter._handlers && emitter._handlers[type] || noHandlers
}
function off(emitter, type, f) {
    if (emitter.removeEventListener) {
        emitter.removeEventListener(type, f, false);
    } else if (emitter.detachEvent) {
        emitter.detachEvent("on" + type, f);
    } else {
        var map$$1 = emitter._handlers, arr = map$$1 && map$$1[type];
        if (arr) {
            var index = indexOf(arr, f);
            if (index > -1) {
                map$$1[type] = arr.slice(0, index).concat(arr.slice(index + 1));
            }
        }
    }
}

function signal(emitter, type /*, values...*/) {
    var handlers = getHandlers(emitter, type);
    if (!handlers.length) {
        return
    }
    var args = Array.prototype.slice.call(arguments, 2);
    for (var i = 0; i < handlers.length; ++i) {
        handlers[i].apply(null, args);
    }
}

// The DOM events that CodeMirror handles can be overridden by
// registering a (non-DOM) handler on the src for the event name,
// and preventDefault-ing the event in that handler.
function signalDOMEvent(cm, e, override) {
    if (typeof e == "string") {
        e = {
            type: e, preventDefault: function () {
                this.defaultPrevented = true;
            }
        };
    }
    signal(cm, override || e.type, cm, e);
    return e_defaultPrevented(e) || e.codemirrorIgnore
}

function signalCursorActivity(cm) {
    var arr = cm._handlers && cm._handlers.cursorActivity;
    if (!arr) {
        return
    }
    var set = cm.curOp.cursorActivityHandlers || (cm.curOp.cursorActivityHandlers = []);
    for (var i = 0; i < arr.length; ++i) {
        if (indexOf(set, arr[i]) == -1) {
            set.push(arr[i]);
        }
    }
}

function hasHandler(emitter, type) {
    return getHandlers(emitter, type).length > 0
}

// Add on and off methods to a constructor's prototype, to make
// registering events on such objects more convenient.
function eventMixin(ctor) {
    ctor.prototype.on = function (type, f) {
        on(this, type, f);
    };
    ctor.prototype.off = function (type, f) {
        off(this, type, f);
    };
}

// Due to the fact that we still support jurassic IE versions, some
// compatibility wrappers are needed.

function e_preventDefault(e) {
    if (e.preventDefault) {
        e.preventDefault();
    } else {
        e.returnValue = false;
    }
}

function e_stopPropagation(e) {
    if (e.stopPropagation) {
        e.stopPropagation();
    } else {
        e.cancelBubble = true;
    }
}

function e_defaultPrevented(e) {
    return e.defaultPrevented != null ? e.defaultPrevented : e.returnValue == false
}

function e_stop(e) {
    e_preventDefault(e);
    e_stopPropagation(e);
}

function e_target(e) {
    return e.target || e.srcElement
}

function e_button(e) {
    var b = e.which;
    if (b == null) {
        if (e.button & 1) {
            b = 1;
        } else if (e.button & 2) {
            b = 3;
        } else if (e.button & 4) {
            b = 2;
        }
    }
    if (mac && e.ctrlKey && b == 1) {
        b = 3;
    }
    return b
}

// Detect drag-and-drop
var dragAndDrop = function () {
    // There is *some* kind of drag-and-drop support in IE6-8, but I
    // couldn't get it to work yet.
    if (ie && ie_version < 9) {
        return false
    }
    var div = elt('div');
    return "draggable" in div || "dragDrop" in div
}();

var zwspSupported;

function zeroWidthElement(measure) {
    if (zwspSupported == null) {
        var test = elt("span", "\u200b");
        removeChildrenAndAdd(measure, elt("span", [test, document.createTextNode("x")]));
        if (measure.firstChild.offsetHeight != 0) {
            zwspSupported = test.offsetWidth <= 1 && test.offsetHeight > 2 && !(ie && ie_version < 8);
        }
    }
    var node = zwspSupported ? elt("span", "\u200b") :
        elt("span", "\u00a0", null, "display: inline-block; width: 1px; margin-right: -1px");
    node.setAttribute("cm-text", "");
    return node
}

// Feature-detect IE's crummy client rect reporting for bidi text
var badBidiRects;

function hasBadBidiRects(measure) {
    if (badBidiRects != null) {
        return badBidiRects
    }
    var txt = removeChildrenAndAdd(measure, document.createTextNode("A\u062eA"));
    var r0 = range(txt, 0, 1).getBoundingClientRect();
    var r1 = range(txt, 1, 2).getBoundingClientRect();
    removeChildren(measure);
    if (!r0 || r0.left == r0.right) {
        return false
    } // Safari returns null in some cases (#2780)
    return badBidiRects = (r1.right - r0.right < 3)
}

// See if "".split is the broken IE version, if so, provide an
// alternative way to split lines.
var splitLinesAuto = "\n\nb".split(/\n/).length != 3 ? function (string) {
    var pos = 0, result = [], l = string.length;
    while (pos <= l) {
        var nl = string.indexOf("\n", pos);
        if (nl == -1) {
            nl = string.length;
        }
        var line = string.slice(pos, string.charAt(nl - 1) == "\r" ? nl - 1 : nl);
        var rt = line.indexOf("\r");
        if (rt != -1) {
            result.push(line.slice(0, rt));
            pos += rt + 1;
        } else {
            result.push(line);
            pos = nl + 1;
        }
    }
    return result
} : function (string) {
    return string.split(/\r\n?|\n/);
};

var hasSelection = window.getSelection ? function (te) {
    try {
        return te.selectionStart != te.selectionEnd
    } catch (e) {
        return false
    }
} : function (te) {
    var range$$1;
    try {
        range$$1 = te.ownerDocument.selection.createRange();
    } catch (e) {
    }
    if (!range$$1 || range$$1.parentElement() != te) {
        return false
    }
    return range$$1.compareEndPoints("StartToEnd", range$$1) != 0
};

var hasCopyEvent = (function () {
    var e = elt("div");
    if ("oncopy" in e) {
        return true
    }
    e.setAttribute("oncopy", "return;");
    return typeof e.oncopy == "function"
})();

var badZoomedRects = null;

function hasBadZoomedRects(measure) {
    if (badZoomedRects != null) {
        return badZoomedRects
    }
    var node = removeChildrenAndAdd(measure, elt("span", "x"));
    var normal = node.getBoundingClientRect();
    var fromRange = range(node, 0, 1).getBoundingClientRect();
    return badZoomedRects = Math.abs(normal.left - fromRange.left) > 1
}

// Known modes, by name and by MIME
var modes = {}, mimeModes = {};

// Extra arguments are stored as the mode's dependencies, which is
// used by (legacy) mechanisms like loadmode.js to automatically
// load a mode. (Preferred mechanism is the require/define calls.)
function defineMode(name, mode) {
    if (arguments.length > 2) {
        mode.dependencies = Array.prototype.slice.call(arguments, 2);
    }
    modes[name] = mode;
}

function defineMIME(mime, spec) {
    mimeModes[mime] = spec;
}

// Given a MIME type, a {name, ...options} config object, or a name
// string, return a mode config object.
function resolveMode(spec) {
    if (typeof spec == "string" && mimeModes.hasOwnProperty(spec)) {
        spec = mimeModes[spec];
    } else if (spec && typeof spec.name == "string" && mimeModes.hasOwnProperty(spec.name)) {
        var found = mimeModes[spec.name];
        if (typeof found == "string") {
            found = {name: found};
        }
        spec = createObj(found, spec);
        spec.name = found.name;
    } else if (typeof spec == "string" && /^[\w\-]+\/[\w\-]+\+xml$/.test(spec)) {
        return resolveMode("application/xml")
    } else if (typeof spec == "string" && /^[\w\-]+\/[\w\-]+\+json$/.test(spec)) {
        return resolveMode("application/json")
    }
    if (typeof spec == "string") {
        return {name: spec}
    } else {
        return spec || {name: "null"}
    }
}

// Given a mode spec (anything that resolveMode accepts), find and
// initialize an actual mode object.
function getMode(options, spec) {
    spec = resolveMode(spec);
    var mfactory = modes[spec.name];
    if (!mfactory) {
        return getMode(options, "text/plain")
    }
    var modeObj = mfactory(options, spec);
    if (modeExtensions.hasOwnProperty(spec.name)) {
        var exts = modeExtensions[spec.name];
        for (var prop in exts) {
            if (!exts.hasOwnProperty(prop)) {
                continue
            }
            if (modeObj.hasOwnProperty(prop)) {
                modeObj["_" + prop] = modeObj[prop];
            }
            modeObj[prop] = exts[prop];
        }
    }
    modeObj.name = spec.name;
    if (spec.helperType) {
        modeObj.helperType = spec.helperType;
    }
    if (spec.modeProps) {
        for (var prop$1 in spec.modeProps) {
            modeObj[prop$1] = spec.modeProps[prop$1];
        }
    }

    return modeObj
}

// This can be used to attach properties to mode objects from
// outside the actual mode definition.
var modeExtensions = {};

function extendMode(mode, properties) {
    var exts = modeExtensions.hasOwnProperty(mode) ? modeExtensions[mode] : (modeExtensions[mode] = {});
    copyObj(properties, exts);
}

function copyState(mode, state) {
    if (state === true) {
        return state
    }
    if (mode.copyState) {
        return mode.copyState(state)
    }
    var nstate = {};
    for (var n in state) {
        var val = state[n];
        if (val instanceof Array) {
            val = val.concat([]);
        }
        nstate[n] = val;
    }
    return nstate
}

// Given a mode and a state (for that mode), find the inner mode and
// state at the position that the state refers to.
function innerMode(mode, state) {
    var info;
    while (mode.innerMode) {
        info = mode.innerMode(state);
        if (!info || info.mode == mode) {
            break
        }
        state = info.state;
        mode = info.mode;
    }
    return info || {mode: mode, state: state}
}

function startState(mode, a1, a2) {
    return mode.startState ? mode.startState(a1, a2) : true
}

// STRING STREAM

// Fed to the mode parsers, provides helper functions to make
// parsers more succinct.

var StringStream = function (string, tabSize, lineOracle) {
    this.pos = this.start = 0;
    this.string = string;
    this.tabSize = tabSize || 8;
    this.lastColumnPos = this.lastColumnValue = 0;
    this.lineStart = 0;
    this.lineOracle = lineOracle;
};

StringStream.prototype.eol = function () {
    return this.pos >= this.string.length
};
StringStream.prototype.sol = function () {
    return this.pos == this.lineStart
};
StringStream.prototype.peek = function () {
    return this.string.charAt(this.pos) || undefined
};
StringStream.prototype.next = function () {
    if (this.pos < this.string.length) {
        return this.string.charAt(this.pos++)
    }
};
StringStream.prototype.eat = function (match) {
    var ch = this.string.charAt(this.pos);
    var ok;
    if (typeof match == "string") {
        ok = ch == match;
    } else {
        ok = ch && (match.test ? match.test(ch) : match(ch));
    }
    if (ok) {
        ++this.pos;
        return ch
    }
};
StringStream.prototype.eatWhile = function (match) {
    var start = this.pos;
    while (this.eat(match)) {
    }
    return this.pos > start
};
StringStream.prototype.eatSpace = function () {
    var this$1 = this;

    var start = this.pos;
    while (/[\s\u00a0]/.test(this.string.charAt(this.pos))) {
        ++this$1.pos;
    }
    return this.pos > start
};
StringStream.prototype.skipToEnd = function () {
    this.pos = this.string.length;
};
StringStream.prototype.skipTo = function (ch) {
    var found = this.string.indexOf(ch, this.pos);
    if (found > -1) {
        this.pos = found;
        return true
    }
};
StringStream.prototype.backUp = function (n) {
    this.pos -= n;
};
StringStream.prototype.column = function () {
    if (this.lastColumnPos < this.start) {
        this.lastColumnValue = countColumn(this.string, this.start, this.tabSize, this.lastColumnPos, this.lastColumnValue);
        this.lastColumnPos = this.start;
    }
    return this.lastColumnValue - (this.lineStart ? countColumn(this.string, this.lineStart, this.tabSize) : 0)
};
StringStream.prototype.indentation = function () {
    return countColumn(this.string, null, this.tabSize) -
        (this.lineStart ? countColumn(this.string, this.lineStart, this.tabSize) : 0)
};
StringStream.prototype.match = function (pattern, consume, caseInsensitive) {
    if (typeof pattern == "string") {
        var cased = function (str) {
            return caseInsensitive ? str.toLowerCase() : str;
        };
        var substr = this.string.substr(this.pos, pattern.length);
        if (cased(substr) == cased(pattern)) {
            if (consume !== false) {
                this.pos += pattern.length;
            }
            return true
        }
    } else {
        var match = this.string.slice(this.pos).match(pattern);
        if (match && match.index > 0) {
            return null
        }
        if (match && consume !== false) {
            this.pos += match[0].length;
        }
        return match
    }
};
StringStream.prototype.current = function () {
    return this.string.slice(this.start, this.pos)
};
StringStream.prototype.hideFirstChars = function (n, inner) {
    this.lineStart += n;
    try {
        return inner()
    } finally {
        this.lineStart -= n;
    }
};
StringStream.prototype.lookAhead = function (n) {
    var oracle = this.lineOracle;
    return oracle && oracle.lookAhead(n)
};
StringStream.prototype.baseToken = function () {
    var oracle = this.lineOracle;
    return oracle && oracle.baseToken(this.pos)
};

// Find the line object corresponding to the given line number.
function getLine(doc, n) {
    n -= doc.first;
    if (n < 0 || n >= doc.size) {
        throw new Error("There is no line " + (n + doc.first) + " in the document.")
    }
    var chunk = doc;
    while (!chunk.lines) {
        for (var i = 0; ; ++i) {
            var child = chunk.children[i], sz = child.chunkSize();
            if (n < sz) {
                chunk = child;
                break
            }
            n -= sz;
        }
    }
    return chunk.lines[n]
}

// Get the part of a document between two positions, as an array of
// strings.
function getBetween(doc, start, end) {
    var out = [], n = start.line;
    doc.iter(start.line, end.line + 1, function (line) {
        var text = line.text;
        if (n == end.line) {
            text = text.slice(0, end.ch);
        }
        if (n == start.line) {
            text = text.slice(start.ch);
        }
        out.push(text);
        ++n;
    });
    return out
}

// Get the lines between from and to, as array of strings.
function getLines(doc, from, to) {
    var out = [];
    doc.iter(from, to, function (line) {
        out.push(line.text);
    }); // iter aborts when callback returns truthy value
    return out
}

// Update the height of a line, propagating the height change
// upwards to parent nodes.
function updateLineHeight(line, height) {
    var diff = height - line.height;
    if (diff) {
        for (var n = line; n; n = n.parent) {
            n.height += diff;
        }
    }
}

// Given a line object, find its line number by walking up through
// its parent links.
function lineNo(line) {
    if (line.parent == null) {
        return null
    }
    var cur = line.parent, no = indexOf(cur.lines, line);
    for (var chunk = cur.parent; chunk; cur = chunk, chunk = chunk.parent) {
        for (var i = 0; ; ++i) {
            if (chunk.children[i] == cur) {
                break
            }
            no += chunk.children[i].chunkSize();
        }
    }
    return no + cur.first
}

// Find the line at the given vertical position, using the height
// information in the document tree.
function lineAtHeight(chunk, h) {
    var n = chunk.first;
    outer: do {
        for (var i$1 = 0; i$1 < chunk.children.length; ++i$1) {
            var child = chunk.children[i$1], ch = child.height;
            if (h < ch) {
                chunk = child;
                continue outer
            }
            h -= ch;
            n += child.chunkSize();
        }
        return n
    } while (!chunk.lines)
    var i = 0;
    for (; i < chunk.lines.length; ++i) {
        var line = chunk.lines[i], lh = line.height;
        if (h < lh) {
            break
        }
        h -= lh;
    }
    return n + i
}

function isLine(doc, l) {
    return l >= doc.first && l < doc.first + doc.size
}

function lineNumberFor(options, i) {
    return String(options.lineNumberFormatter(i + options.firstLineNumber))
}

// A Pos instance represents a position within the text.
function Pos(line, ch, sticky) {
    if (sticky === void 0) sticky = null;

    if (!(this instanceof Pos)) {
        return new Pos(line, ch, sticky)
    }
    this.line = line;
    this.ch = ch;
    this.sticky = sticky;
}

// Compare two positions, return 0 if they are the same, a negative
// number when a is less, and a positive number otherwise.
function cmp(a, b) {
    return a.line - b.line || a.ch - b.ch
}

function equalCursorPos(a, b) {
    return a.sticky == b.sticky && cmp(a, b) == 0
}

function copyPos(x) {
    return Pos(x.line, x.ch)
}

function maxPos(a, b) {
    return cmp(a, b) < 0 ? b : a
}

function minPos(a, b) {
    return cmp(a, b) < 0 ? a : b
}

// Most of the external API clips given positions to make sure they
// actually exist within the document.
function clipLine(doc, n) {
    return Math.max(doc.first, Math.min(n, doc.first + doc.size - 1))
}

function clipPos(doc, pos) {
    if (pos.line < doc.first) {
        return Pos(doc.first, 0)
    }
    var last = doc.first + doc.size - 1;
    if (pos.line > last) {
        return Pos(last, getLine(doc, last).text.length)
    }
    return clipToLen(pos, getLine(doc, pos.line).text.length)
}

function clipToLen(pos, linelen) {
    var ch = pos.ch;
    if (ch == null || ch > linelen) {
        return Pos(pos.line, linelen)
    } else if (ch < 0) {
        return Pos(pos.line, 0)
    } else {
        return pos
    }
}

function clipPosArray(doc, array) {
    var out = [];
    for (var i = 0; i < array.length; i++) {
        out[i] = clipPos(doc, array[i]);
    }
    return out
}

var SavedContext = function (state, lookAhead) {
    this.state = state;
    this.lookAhead = lookAhead;
};

var Context = function (doc, state, line, lookAhead) {
    this.state = state;
    this.doc = doc;
    this.line = line;
    this.maxLookAhead = lookAhead || 0;
    this.baseTokens = null;
    this.baseTokenPos = 1;
};

Context.prototype.lookAhead = function (n) {
    var line = this.doc.getLine(this.line + n);
    if (line != null && n > this.maxLookAhead) {
        this.maxLookAhead = n;
    }
    return line
};

Context.prototype.baseToken = function (n) {
    var this$1 = this;

    if (!this.baseTokens) {
        return null
    }
    while (this.baseTokens[this.baseTokenPos] <= n) {
        this$1.baseTokenPos += 2;
    }
    var type = this.baseTokens[this.baseTokenPos + 1];
    return {
        type: type && type.replace(/( |^)overlay .*/, ""),
        size: this.baseTokens[this.baseTokenPos] - n
    }
};

Context.prototype.nextLine = function () {
    this.line++;
    if (this.maxLookAhead > 0) {
        this.maxLookAhead--;
    }
};

Context.fromSaved = function (doc, saved, line) {
    if (saved instanceof SavedContext) {
        return new Context(doc, copyState(doc.mode, saved.state), line, saved.lookAhead)
    } else {
        return new Context(doc, copyState(doc.mode, saved), line)
    }
};

Context.prototype.save = function (copy) {
    var state = copy !== false ? copyState(this.doc.mode, this.state) : this.state;
    return this.maxLookAhead > 0 ? new SavedContext(state, this.maxLookAhead) : state
};


// Compute a style array (an array starting with a mode generation
// -- for invalidation -- followed by pairs of end positions and
// style strings), which is used to highlight the tokens on the
// line.
function highlightLine(cm, line, context, forceToEnd) {
    // A styles array always starts with a number identifying the
    // mode/overlays that it is based on (for easy invalidation).
    var st = [cm.state.modeGen], lineClasses = {};
    // Compute the base array of styles
    runMode(cm, line.text, cm.doc.mode, context, function (end, style) {
            return st.push(end, style);
        },
        lineClasses, forceToEnd);
    var state = context.state;

    // Run overlays, adjust style array.
    var loop = function (o) {
        context.baseTokens = st;
        var overlay = cm.state.overlays[o], i = 1, at = 0;
        context.state = true;
        runMode(cm, line.text, overlay.mode, context, function (end, style) {
            var start = i;
            // Ensure there's a token end at the current position, and that i points at it
            while (at < end) {
                var i_end = st[i];
                if (i_end > end) {
                    st.splice(i, 1, end, st[i + 1], i_end);
                }
                i += 2;
                at = Math.min(end, i_end);
            }
            if (!style) {
                return
            }
            if (overlay.opaque) {
                st.splice(start, i - start, end, "overlay " + style);
                i = start + 2;
            } else {
                for (; start < i; start += 2) {
                    var cur = st[start + 1];
                    st[start + 1] = (cur ? cur + " " : "") + "overlay " + style;
                }
            }
        }, lineClasses);
        context.state = state;
        context.baseTokens = null;
        context.baseTokenPos = 1;
    };

    for (var o = 0; o < cm.state.overlays.length; ++o) loop(o);

    return {styles: st, classes: lineClasses.bgClass || lineClasses.textClass ? lineClasses : null}
}

function getLineStyles(cm, line, updateFrontier) {
    if (!line.styles || line.styles[0] != cm.state.modeGen) {
        var context = getContextBefore(cm, lineNo(line));
        var resetState = line.text.length > cm.options.maxHighlightLength && copyState(cm.doc.mode, context.state);
        var result = highlightLine(cm, line, context);
        if (resetState) {
            context.state = resetState;
        }
        line.stateAfter = context.save(!resetState);
        line.styles = result.styles;
        if (result.classes) {
            line.styleClasses = result.classes;
        } else if (line.styleClasses) {
            line.styleClasses = null;
        }
        if (updateFrontier === cm.doc.highlightFrontier) {
            cm.doc.modeFrontier = Math.max(cm.doc.modeFrontier, ++cm.doc.highlightFrontier);
        }
    }
    return line.styles
}

function getContextBefore(cm, n, precise) {
    var doc = cm.doc, display = cm.display;
    if (!doc.mode.startState) {
        return new Context(doc, true, n)
    }
    var start = findStartLine(cm, n, precise);
    var saved = start > doc.first && getLine(doc, start - 1).stateAfter;
    var context = saved ? Context.fromSaved(doc, saved, start) : new Context(doc, startState(doc.mode), start);

    doc.iter(start, n, function (line) {
        processLine(cm, line.text, context);
        var pos = context.line;
        line.stateAfter = pos == n - 1 || pos % 5 == 0 || pos >= display.viewFrom && pos < display.viewTo ? context.save() : null;
        context.nextLine();
    });
    if (precise) {
        doc.modeFrontier = context.line;
    }
    return context
}

// Lightweight form of highlight -- proceed over this line and
// update state, but don't save a style array. Used for lines that
// aren't currently visible.
function processLine(cm, text, context, startAt) {
    var mode = cm.doc.mode;
    var stream = new StringStream(text, cm.options.tabSize, context);
    stream.start = stream.pos = startAt || 0;
    if (text == "") {
        callBlankLine(mode, context.state);
    }
    while (!stream.eol()) {
        readToken(mode, stream, context.state);
        stream.start = stream.pos;
    }
}

function callBlankLine(mode, state) {
    if (mode.blankLine) {
        return mode.blankLine(state)
    }
    if (!mode.innerMode) {
        return
    }
    var inner = innerMode(mode, state);
    if (inner.mode.blankLine) {
        return inner.mode.blankLine(inner.state)
    }
}

function readToken(mode, stream, state, inner) {
    for (var i = 0; i < 10; i++) {
        if (inner) {
            inner[0] = innerMode(mode, state).mode;
        }
        var style = mode.token(stream, state);
        if (stream.pos > stream.start) {
            return style
        }
    }
    throw new Error("Mode " + mode.name + " failed to advance stream.")
}

var Token = function (stream, type, state) {
    this.start = stream.start;
    this.end = stream.pos;
    this.string = stream.current();
    this.type = type || null;
    this.state = state;
};

// Utility for getTokenAt and getLineTokens
function takeToken(cm, pos, precise, asArray) {
    var doc = cm.doc, mode = doc.mode, style;
    pos = clipPos(doc, pos);
    var line = getLine(doc, pos.line), context = getContextBefore(cm, pos.line, precise);
    var stream = new StringStream(line.text, cm.options.tabSize, context), tokens;
    if (asArray) {
        tokens = [];
    }
    while ((asArray || stream.pos < pos.ch) && !stream.eol()) {
        stream.start = stream.pos;
        style = readToken(mode, stream, context.state);
        if (asArray) {
            tokens.push(new Token(stream, style, copyState(doc.mode, context.state)));
        }
    }
    return asArray ? tokens : new Token(stream, style, context.state)
}

function extractLineClasses(type, output) {
    if (type) {
        for (; ;) {
            var lineClass = type.match(/(?:^|\s+)line-(background-)?(\S+)/);
            if (!lineClass) {
                break
            }
            type = type.slice(0, lineClass.index) + type.slice(lineClass.index + lineClass[0].length);
            var prop = lineClass[1] ? "bgClass" : "textClass";
            if (output[prop] == null) {
                output[prop] = lineClass[2];
            } else if (!(new RegExp("(?:^|\s)" + lineClass[2] + "(?:$|\s)")).test(output[prop])) {
                output[prop] += " " + lineClass[2];
            }
        }
    }
    return type
}

// Run the given mode's parser over a line, calling f for each token.
function runMode(cm, text, mode, context, f, lineClasses, forceToEnd) {
    var flattenSpans = mode.flattenSpans;
    if (flattenSpans == null) {
        flattenSpans = cm.options.flattenSpans;
    }
    var curStart = 0, curStyle = null;
    var stream = new StringStream(text, cm.options.tabSize, context), style;
    var inner = cm.options.addModeClass && [null];
    if (text == "") {
        extractLineClasses(callBlankLine(mode, context.state), lineClasses);
    }
    while (!stream.eol()) {
        if (stream.pos > cm.options.maxHighlightLength) {
            flattenSpans = false;
            if (forceToEnd) {
                processLine(cm, text, context, stream.pos);
            }
            stream.pos = text.length;
            style = null;
        } else {
            style = extractLineClasses(readToken(mode, stream, context.state, inner), lineClasses);
        }
        if (inner) {
            var mName = inner[0].name;
            if (mName) {
                style = "m-" + (style ? mName + " " + style : mName);
            }
        }
        if (!flattenSpans || curStyle != style) {
            while (curStart < stream.start) {
                curStart = Math.min(stream.start, curStart + 5000);
                f(curStart, curStyle);
            }
            curStyle = style;
        }
        stream.start = stream.pos;
    }
    while (curStart < stream.pos) {
        // Webkit seems to refuse to render text nodes longer than 57444
        // characters, and returns inaccurate measurements in nodes
        // starting around 5000 chars.
        var pos = Math.min(stream.pos, curStart + 5000);
        f(pos, curStyle);
        curStart = pos;
    }
}

// Finds the line to start with when starting a parse. Tries to
// find a line with a stateAfter, so that it can start with a
// valid state. If that fails, it returns the line with the
// smallest indentation, which tends to need the least context to
// parse correctly.
function findStartLine(cm, n, precise) {
    var minindent, minline, doc = cm.doc;
    var lim = precise ? -1 : n - (cm.doc.mode.innerMode ? 1000 : 100);
    for (var search = n; search > lim; --search) {
        if (search <= doc.first) {
            return doc.first
        }
        var line = getLine(doc, search - 1), after = line.stateAfter;
        if (after && (!precise || search + (after instanceof SavedContext ? after.lookAhead : 0) <= doc.modeFrontier)) {
            return search
        }
        var indented = countColumn(line.text, null, cm.options.tabSize);
        if (minline == null || minindent > indented) {
            minline = search - 1;
            minindent = indented;
        }
    }
    return minline
}

function retreatFrontier(doc, n) {
    doc.modeFrontier = Math.min(doc.modeFrontier, n);
    if (doc.highlightFrontier < n - 10) {
        return
    }
    var start = doc.first;
    for (var line = n - 1; line > start; line--) {
        var saved = getLine(doc, line).stateAfter;
        // change is on 3
        // state on line 1 looked ahead 2 -- so saw 3
        // test 1 + 2 < 3 should cover this
        if (saved && (!(saved instanceof SavedContext) || line + saved.lookAhead < n)) {
            start = line + 1;
            break
        }
    }
    doc.highlightFrontier = Math.min(doc.highlightFrontier, start);
}

// Optimize some code when these features are not used.
var sawReadOnlySpans = false, sawCollapsedSpans = false;

function seeReadOnlySpans() {
    sawReadOnlySpans = true;
}

function seeCollapsedSpans() {
    sawCollapsedSpans = true;
}

// TEXTMARKER SPANS

function MarkedSpan(marker, from, to) {
    this.marker = marker;
    this.from = from;
    this.to = to;
}

// Search an array of spans for a span matching the given marker.
function getMarkedSpanFor(spans, marker) {
    if (spans) {
        for (var i = 0; i < spans.length; ++i) {
            var span = spans[i];
            if (span.marker == marker) {
                return span
            }
        }
    }
}

// Remove a span from an array, returning undefined if no spans are
// left (we don't store arrays for lines without spans).
function removeMarkedSpan(spans, span) {
    var r;
    for (var i = 0; i < spans.length; ++i) {
        if (spans[i] != span) {
            (r || (r = [])).push(spans[i]);
        }
    }
    return r
}

// Add a span to a line.
function addMarkedSpan(line, span) {
    line.markedSpans = line.markedSpans ? line.markedSpans.concat([span]) : [span];
    span.marker.attachLine(line);
}

// Used for the algorithm that adjusts markers for a change in the
// document. These functions cut an array of spans at a given
// character position, returning an array of remaining chunks (or
// undefined if nothing remains).
function markedSpansBefore(old, startCh, isInsert) {
    var nw;
    if (old) {
        for (var i = 0; i < old.length; ++i) {
            var span = old[i], marker = span.marker;
            var startsBefore = span.from == null || (marker.inclusiveLeft ? span.from <= startCh : span.from < startCh);
            if (startsBefore || span.from == startCh && marker.type == "bookmark" && (!isInsert || !span.marker.insertLeft)) {
                var endsAfter = span.to == null || (marker.inclusiveRight ? span.to >= startCh : span.to > startCh)
                ;(nw || (nw = [])).push(new MarkedSpan(marker, span.from, endsAfter ? null : span.to));
            }
        }
    }
    return nw
}

function markedSpansAfter(old, endCh, isInsert) {
    var nw;
    if (old) {
        for (var i = 0; i < old.length; ++i) {
            var span = old[i], marker = span.marker;
            var endsAfter = span.to == null || (marker.inclusiveRight ? span.to >= endCh : span.to > endCh);
            if (endsAfter || span.from == endCh && marker.type == "bookmark" && (!isInsert || span.marker.insertLeft)) {
                var startsBefore = span.from == null || (marker.inclusiveLeft ? span.from <= endCh : span.from < endCh)
                ;(nw || (nw = [])).push(new MarkedSpan(marker, startsBefore ? null : span.from - endCh,
                    span.to == null ? null : span.to - endCh));
            }
        }
    }
    return nw
}

// Given a change object, compute the new set of marker spans that
// cover the line in which the change took place. Removes spans
// entirely within the change, reconnects spans belonging to the
// same marker that appear on both sides of the change, and cuts off
// spans partially within the change. Returns an array of span
// arrays with one element for each line in (after) the change.
function stretchSpansOverChange(doc, change) {
    if (change.full) {
        return null
    }
    var oldFirst = isLine(doc, change.from.line) && getLine(doc, change.from.line).markedSpans;
    var oldLast = isLine(doc, change.to.line) && getLine(doc, change.to.line).markedSpans;
    if (!oldFirst && !oldLast) {
        return null
    }

    var startCh = change.from.ch, endCh = change.to.ch, isInsert = cmp(change.from, change.to) == 0;
    // Get the spans that 'stick out' on both sides
    var first = markedSpansBefore(oldFirst, startCh, isInsert);
    var last = markedSpansAfter(oldLast, endCh, isInsert);

    // Next, merge those two ends
    var sameLine = change.text.length == 1, offset = lst(change.text).length + (sameLine ? startCh : 0);
    if (first) {
        // Fix up .to properties of first
        for (var i = 0; i < first.length; ++i) {
            var span = first[i];
            if (span.to == null) {
                var found = getMarkedSpanFor(last, span.marker);
                if (!found) {
                    span.to = startCh;
                } else if (sameLine) {
                    span.to = found.to == null ? null : found.to + offset;
                }
            }
        }
    }
    if (last) {
        // Fix up .from in last (or move them into first in case of sameLine)
        for (var i$1 = 0; i$1 < last.length; ++i$1) {
            var span$1 = last[i$1];
            if (span$1.to != null) {
                span$1.to += offset;
            }
            if (span$1.from == null) {
                var found$1 = getMarkedSpanFor(first, span$1.marker);
                if (!found$1) {
                    span$1.from = offset;
                    if (sameLine) {
                        (first || (first = [])).push(span$1);
                    }
                }
            } else {
                span$1.from += offset;
                if (sameLine) {
                    (first || (first = [])).push(span$1);
                }
            }
        }
    }
    // Make sure we didn't create any zero-length spans
    if (first) {
        first = clearEmptySpans(first);
    }
    if (last && last != first) {
        last = clearEmptySpans(last);
    }

    var newMarkers = [first];
    if (!sameLine) {
        // Fill gap with whole-line-spans
        var gap = change.text.length - 2, gapMarkers;
        if (gap > 0 && first) {
            for (var i$2 = 0; i$2 < first.length; ++i$2) {
                if (first[i$2].to == null) {
                    (gapMarkers || (gapMarkers = [])).push(new MarkedSpan(first[i$2].marker, null, null));
                }
            }
        }
        for (var i$3 = 0; i$3 < gap; ++i$3) {
            newMarkers.push(gapMarkers);
        }
        newMarkers.push(last);
    }
    return newMarkers
}

// Remove spans that are empty and don't have a clearWhenEmpty
// option of false.
function clearEmptySpans(spans) {
    for (var i = 0; i < spans.length; ++i) {
        var span = spans[i];
        if (span.from != null && span.from == span.to && span.marker.clearWhenEmpty !== false) {
            spans.splice(i--, 1);
        }
    }
    if (!spans.length) {
        return null
    }
    return spans
}

// Used to 'clip' out readOnly ranges when making a change.
function removeReadOnlyRanges(doc, from, to) {
    var markers = null;
    doc.iter(from.line, to.line + 1, function (line) {
        if (line.markedSpans) {
            for (var i = 0; i < line.markedSpans.length; ++i) {
                var mark = line.markedSpans[i].marker;
                if (mark.readOnly && (!markers || indexOf(markers, mark) == -1)) {
                    (markers || (markers = [])).push(mark);
                }
            }
        }
    });
    if (!markers) {
        return null
    }
    var parts = [{from: from, to: to}];
    for (var i = 0; i < markers.length; ++i) {
        var mk = markers[i], m = mk.find(0);
        for (var j = 0; j < parts.length; ++j) {
            var p = parts[j];
            if (cmp(p.to, m.from) < 0 || cmp(p.from, m.to) > 0) {
                continue
            }
            var newParts = [j, 1], dfrom = cmp(p.from, m.from), dto = cmp(p.to, m.to);
            if (dfrom < 0 || !mk.inclusiveLeft && !dfrom) {
                newParts.push({from: p.from, to: m.from});
            }
            if (dto > 0 || !mk.inclusiveRight && !dto) {
                newParts.push({from: m.to, to: p.to});
            }
            parts.splice.apply(parts, newParts);
            j += newParts.length - 3;
        }
    }
    return parts
}

// Connect or disconnect spans from a line.
function detachMarkedSpans(line) {
    var spans = line.markedSpans;
    if (!spans) {
        return
    }
    for (var i = 0; i < spans.length; ++i) {
        spans[i].marker.detachLine(line);
    }
    line.markedSpans = null;
}

function attachMarkedSpans(line, spans) {
    if (!spans) {
        return
    }
    for (var i = 0; i < spans.length; ++i) {
        spans[i].marker.attachLine(line);
    }
    line.markedSpans = spans;
}

// Helpers used when computing which overlapping collapsed span
// counts as the larger one.
function extraLeft(marker) {
    return marker.inclusiveLeft ? -1 : 0
}

function extraRight(marker) {
    return marker.inclusiveRight ? 1 : 0
}

// Returns a number indicating which of two overlapping collapsed
// spans is larger (and thus includes the other). Falls back to
// comparing ids when the spans cover exactly the same range.
function compareCollapsedMarkers(a, b) {
    var lenDiff = a.lines.length - b.lines.length;
    if (lenDiff != 0) {
        return lenDiff
    }
    var aPos = a.find(), bPos = b.find();
    var fromCmp = cmp(aPos.from, bPos.from) || extraLeft(a) - extraLeft(b);
    if (fromCmp) {
        return -fromCmp
    }
    var toCmp = cmp(aPos.to, bPos.to) || extraRight(a) - extraRight(b);
    if (toCmp) {
        return toCmp
    }
    return b.id - a.id
}

// Find out whether a line ends or starts in a collapsed span. If
// so, return the marker for that span.
function collapsedSpanAtSide(line, start) {
    var sps = sawCollapsedSpans && line.markedSpans, found;
    if (sps) {
        for (var sp = (void 0), i = 0; i < sps.length; ++i) {
            sp = sps[i];
            if (sp.marker.collapsed && (start ? sp.from : sp.to) == null &&
                (!found || compareCollapsedMarkers(found, sp.marker) < 0)) {
                found = sp.marker;
            }
        }
    }
    return found
}

function collapsedSpanAtStart(line) {
    return collapsedSpanAtSide(line, true)
}

function collapsedSpanAtEnd(line) {
    return collapsedSpanAtSide(line, false)
}

function collapsedSpanAround(line, ch) {
    var sps = sawCollapsedSpans && line.markedSpans, found;
    if (sps) {
        for (var i = 0; i < sps.length; ++i) {
            var sp = sps[i];
            if (sp.marker.collapsed && (sp.from == null || sp.from < ch) && (sp.to == null || sp.to > ch) &&
                (!found || compareCollapsedMarkers(found, sp.marker) < 0)) {
                found = sp.marker;
            }
        }
    }
    return found
}

// Test whether there exists a collapsed span that partially
// overlaps (covers the start or end, but not both) of a new span.
// Such overlap is not allowed.
function conflictingCollapsedRange(doc, lineNo$$1, from, to, marker) {
    var line = getLine(doc, lineNo$$1);
    var sps = sawCollapsedSpans && line.markedSpans;
    if (sps) {
        for (var i = 0; i < sps.length; ++i) {
            var sp = sps[i];
            if (!sp.marker.collapsed) {
                continue
            }
            var found = sp.marker.find(0);
            var fromCmp = cmp(found.from, from) || extraLeft(sp.marker) - extraLeft(marker);
            var toCmp = cmp(found.to, to) || extraRight(sp.marker) - extraRight(marker);
            if (fromCmp >= 0 && toCmp <= 0 || fromCmp <= 0 && toCmp >= 0) {
                continue
            }
            if (fromCmp <= 0 && (sp.marker.inclusiveRight && marker.inclusiveLeft ? cmp(found.to, from) >= 0 : cmp(found.to, from) > 0) ||
                fromCmp >= 0 && (sp.marker.inclusiveRight && marker.inclusiveLeft ? cmp(found.from, to) <= 0 : cmp(found.from, to) < 0)) {
                return true
            }
        }
    }
}

// A visual line is a line as drawn on the screen. Folding, for
// example, can cause multiple logical lines to appear on the same
// visual line. This finds the start of the visual line that the
// given line is part of (usually that is the line itself).
function visualLine(line) {
    var merged;
    while (merged = collapsedSpanAtStart(line)) {
        line = merged.find(-1, true).line;
    }
    return line
}

function visualLineEnd(line) {
    var merged;
    while (merged = collapsedSpanAtEnd(line)) {
        line = merged.find(1, true).line;
    }
    return line
}

// Returns an array of logical lines that continue the visual line
// started by the argument, or undefined if there are no such lines.
function visualLineContinued(line) {
    var merged, lines;
    while (merged = collapsedSpanAtEnd(line)) {
        line = merged.find(1, true).line
        ;(lines || (lines = [])).push(line);
    }
    return lines
}

// Get the line number of the start of the visual line that the
// given line number is part of.
function visualLineNo(doc, lineN) {
    var line = getLine(doc, lineN), vis = visualLine(line);
    if (line == vis) {
        return lineN
    }
    return lineNo(vis)
}

// Get the line number of the start of the next visual line after
// the given line.
function visualLineEndNo(doc, lineN) {
    if (lineN > doc.lastLine()) {
        return lineN
    }
    var line = getLine(doc, lineN), merged;
    if (!lineIsHidden(doc, line)) {
        return lineN
    }
    while (merged = collapsedSpanAtEnd(line)) {
        line = merged.find(1, true).line;
    }
    return lineNo(line) + 1
}

// Compute whether a line is hidden. Lines count as hidden when they
// are part of a visual line that starts with another line, or when
// they are entirely covered by collapsed, non-widget span.
function lineIsHidden(doc, line) {
    var sps = sawCollapsedSpans && line.markedSpans;
    if (sps) {
        for (var sp = (void 0), i = 0; i < sps.length; ++i) {
            sp = sps[i];
            if (!sp.marker.collapsed) {
                continue
            }
            if (sp.from == null) {
                return true
            }
            if (sp.marker.widgetNode) {
                continue
            }
            if (sp.from == 0 && sp.marker.inclusiveLeft && lineIsHiddenInner(doc, line, sp)) {
                return true
            }
        }
    }
}

function lineIsHiddenInner(doc, line, span) {
    if (span.to == null) {
        var end = span.marker.find(1, true);
        return lineIsHiddenInner(doc, end.line, getMarkedSpanFor(end.line.markedSpans, span.marker))
    }
    if (span.marker.inclusiveRight && span.to == line.text.length) {
        return true
    }
    for (var sp = (void 0), i = 0; i < line.markedSpans.length; ++i) {
        sp = line.markedSpans[i];
        if (sp.marker.collapsed && !sp.marker.widgetNode && sp.from == span.to &&
            (sp.to == null || sp.to != span.from) &&
            (sp.marker.inclusiveLeft || span.marker.inclusiveRight) &&
            lineIsHiddenInner(doc, line, sp)) {
            return true
        }
    }
}

// Find the height above the given line.
function heightAtLine(lineObj) {
    lineObj = visualLine(lineObj);

    var h = 0, chunk = lineObj.parent;
    for (var i = 0; i < chunk.lines.length; ++i) {
        var line = chunk.lines[i];
        if (line == lineObj) {
            break
        } else {
            h += line.height;
        }
    }
    for (var p = chunk.parent; p; chunk = p, p = chunk.parent) {
        for (var i$1 = 0; i$1 < p.children.length; ++i$1) {
            var cur = p.children[i$1];
            if (cur == chunk) {
                break
            } else {
                h += cur.height;
            }
        }
    }
    return h
}

// Compute the character length of a line, taking into account
// collapsed ranges (see markText) that might hide parts, and join
// other lines onto it.
function lineLength(line) {
    if (line.height == 0) {
        return 0
    }
    var len = line.text.length, merged, cur = line;
    while (merged = collapsedSpanAtStart(cur)) {
        var found = merged.find(0, true);
        cur = found.from.line;
        len += found.from.ch - found.to.ch;
    }
    cur = line;
    while (merged = collapsedSpanAtEnd(cur)) {
        var found$1 = merged.find(0, true);
        len -= cur.text.length - found$1.from.ch;
        cur = found$1.to.line;
        len += cur.text.length - found$1.to.ch;
    }
    return len
}

// Find the longest line in the document.
function findMaxLine(cm) {
    var d = cm.display, doc = cm.doc;
    d.maxLine = getLine(doc, doc.first);
    d.maxLineLength = lineLength(d.maxLine);
    d.maxLineChanged = true;
    doc.iter(function (line) {
        var len = lineLength(line);
        if (len > d.maxLineLength) {
            d.maxLineLength = len;
            d.maxLine = line;
        }
    });
}

// LINE DATA STRUCTURE

// Line objects. These hold state related to a line, including
// highlighting info (the styles array).
var Line = function (text, markedSpans, estimateHeight) {
    this.text = text;
    attachMarkedSpans(this, markedSpans);
    this.height = estimateHeight ? estimateHeight(this) : 1;
};

Line.prototype.lineNo = function () {
    return lineNo(this)
};
eventMixin(Line);

// Change the content (text, markers) of a line. Automatically
// invalidates cached information and tries to re-estimate the
// line's height.
function updateLine(line, text, markedSpans, estimateHeight) {
    line.text = text;
    if (line.stateAfter) {
        line.stateAfter = null;
    }
    if (line.styles) {
        line.styles = null;
    }
    if (line.order != null) {
        line.order = null;
    }
    detachMarkedSpans(line);
    attachMarkedSpans(line, markedSpans);
    var estHeight = estimateHeight ? estimateHeight(line) : 1;
    if (estHeight != line.height) {
        updateLineHeight(line, estHeight);
    }
}

// Detach a line from the document tree and its markers.
function cleanUpLine(line) {
    line.parent = null;
    detachMarkedSpans(line);
}

// Convert a style as returned by a mode (either null, or a string
// containing one or more styles) to a CSS style. This is cached,
// and also looks for line-wide styles.
var styleToClassCache = {}, styleToClassCacheWithMode = {};

function interpretTokenStyle(style, options) {
    if (!style || /^\s*$/.test(style)) {
        return null
    }
    var cache = options.addModeClass ? styleToClassCacheWithMode : styleToClassCache;
    return cache[style] ||
        (cache[style] = style.replace(/\S+/g, "cm-$&"))
}

// Render the DOM representation of the text of a line. Also builds
// up a 'line map', which points at the DOM nodes that represent
// specific stretches of text, and is used by the measuring code.
// The returned object contains the DOM node, this map, and
// information about line-wide styles that were set by the mode.
function buildLineContent(cm, lineView) {
    // The padding-right forces the element to have a 'border', which
    // is needed on Webkit to be able to get line-level bounding
    // rectangles for it (in measureChar).
    var content = eltP("span", null, null, webkit ? "padding-right: .1px" : null);
    var builder = {
        pre: eltP("pre", [content], "CodeMirror-line"), content: content,
        col: 0, pos: 0, cm: cm,
        trailingSpace: false,
        splitSpaces: cm.getOption("lineWrapping")
    };
    lineView.measure = {};

    // Iterate over the logical lines that make up this visual line.
    for (var i = 0; i <= (lineView.rest ? lineView.rest.length : 0); i++) {
        var line = i ? lineView.rest[i - 1] : lineView.line, order = (void 0);
        builder.pos = 0;
        builder.addToken = buildToken;
        // Optionally wire in some hacks into the token-rendering
        // algorithm, to deal with browser quirks.
        if (hasBadBidiRects(cm.display.measure) && (order = getOrder(line, cm.doc.direction))) {
            builder.addToken = buildTokenBadBidi(builder.addToken, order);
        }
        builder.map = [];
        var allowFrontierUpdate = lineView != cm.display.externalMeasured && lineNo(line);
        insertLineContent(line, builder, getLineStyles(cm, line, allowFrontierUpdate));
        if (line.styleClasses) {
            if (line.styleClasses.bgClass) {
                builder.bgClass = joinClasses(line.styleClasses.bgClass, builder.bgClass || "");
            }
            if (line.styleClasses.textClass) {
                builder.textClass = joinClasses(line.styleClasses.textClass, builder.textClass || "");
            }
        }

        // Ensure at least a single node is present, for measuring.
        if (builder.map.length == 0) {
            builder.map.push(0, 0, builder.content.appendChild(zeroWidthElement(cm.display.measure)));
        }

        // Store the map and a cache object for the current logical line
        if (i == 0) {
            lineView.measure.map = builder.map;
            lineView.measure.cache = {};
        } else {
            (lineView.measure.maps || (lineView.measure.maps = [])).push(builder.map)
            ;(lineView.measure.caches || (lineView.measure.caches = [])).push({});
        }
    }

    // See issue #2901
    if (webkit) {
        var last = builder.content.lastChild;
        if (/\bcm-tab\b/.test(last.className) || (last.querySelector && last.querySelector(".cm-tab"))) {
            builder.content.className = "cm-tab-wrap-hack";
        }
    }

    signal(cm, "renderLine", cm, lineView.line, builder.pre);
    if (builder.pre.className) {
        builder.textClass = joinClasses(builder.pre.className, builder.textClass || "");
    }

    return builder
}

function defaultSpecialCharPlaceholder(ch) {
    var token = elt("span", "\u2022", "cm-invalidchar");
    token.title = "\\u" + ch.charCodeAt(0).toString(16);
    token.setAttribute("aria-label", token.title);
    return token
}

// Build up the DOM representation for a single token, and add it to
// the line map. Takes care to render special characters separately.
function buildToken(builder, text, style, startStyle, endStyle, css, attributes) {
    if (!text) {
        return
    }
    var displayText = builder.splitSpaces ? splitSpaces(text, builder.trailingSpace) : text;
    var special = builder.cm.state.specialChars, mustWrap = false;
    var content;
    if (!special.test(text)) {
        builder.col += text.length;
        content = document.createTextNode(displayText);
        builder.map.push(builder.pos, builder.pos + text.length, content);
        if (ie && ie_version < 9) {
            mustWrap = true;
        }
        builder.pos += text.length;
    } else {
        content = document.createDocumentFragment();
        var pos = 0;
        while (true) {
            special.lastIndex = pos;
            var m = special.exec(text);
            var skipped = m ? m.index - pos : text.length - pos;
            if (skipped) {
                var txt = document.createTextNode(displayText.slice(pos, pos + skipped));
                if (ie && ie_version < 9) {
                    content.appendChild(elt("span", [txt]));
                } else {
                    content.appendChild(txt);
                }
                builder.map.push(builder.pos, builder.pos + skipped, txt);
                builder.col += skipped;
                builder.pos += skipped;
            }
            if (!m) {
                break
            }
            pos += skipped + 1;
            var txt$1 = (void 0);
            if (m[0] == "\t") {
                var tabSize = builder.cm.options.tabSize, tabWidth = tabSize - builder.col % tabSize;
                txt$1 = content.appendChild(elt("span", spaceStr(tabWidth), "cm-tab"));
                txt$1.setAttribute("role", "presentation");
                txt$1.setAttribute("cm-text", "\t");
                builder.col += tabWidth;
            } else if (m[0] == "\r" || m[0] == "\n") {
                txt$1 = content.appendChild(elt("span", m[0] == "\r" ? "\u240d" : "\u2424", "cm-invalidchar"));
                txt$1.setAttribute("cm-text", m[0]);
                builder.col += 1;
            } else {
                txt$1 = builder.cm.options.specialCharPlaceholder(m[0]);
                txt$1.setAttribute("cm-text", m[0]);
                if (ie && ie_version < 9) {
                    content.appendChild(elt("span", [txt$1]));
                } else {
                    content.appendChild(txt$1);
                }
                builder.col += 1;
            }
            builder.map.push(builder.pos, builder.pos + 1, txt$1);
            builder.pos++;
        }
    }
    builder.trailingSpace = displayText.charCodeAt(text.length - 1) == 32;
    if (style || startStyle || endStyle || mustWrap || css) {
        var fullStyle = style || "";
        if (startStyle) {
            fullStyle += startStyle;
        }
        if (endStyle) {
            fullStyle += endStyle;
        }
        var token = elt("span", [content], fullStyle, css);
        if (attributes) {
            for (var attr in attributes) {
                if (attributes.hasOwnProperty(attr) && attr != "style" && attr != "class") {
                    token.setAttribute(attr, attributes[attr]);
                }
            }
        }
        return builder.content.appendChild(token)
    }
    builder.content.appendChild(content);
}

// Change some spaces to NBSP to prevent the browser from collapsing
// trailing spaces at the end of a line when rendering text (issue #1362).
function splitSpaces(text, trailingBefore) {
    if (text.length > 1 && !/  /.test(text)) {
        return text
    }
    var spaceBefore = trailingBefore, result = "";
    for (var i = 0; i < text.length; i++) {
        var ch = text.charAt(i);
        if (ch == " " && spaceBefore && (i == text.length - 1 || text.charCodeAt(i + 1) == 32)) {
            ch = "\u00a0";
        }
        result += ch;
        spaceBefore = ch == " ";
    }
    return result
}

// Work around nonsense dimensions being reported for stretches of
// right-to-left text.
function buildTokenBadBidi(inner, order) {
    return function (builder, text, style, startStyle, endStyle, css, attributes) {
        style = style ? style + " cm-force-border" : "cm-force-border";
        var start = builder.pos, end = start + text.length;
        for (; ;) {
            // Find the part that overlaps with the start of this text
            var part = (void 0);
            for (var i = 0; i < order.length; i++) {
                part = order[i];
                if (part.to > start && part.from <= start) {
                    break
                }
            }
            if (part.to >= end) {
                return inner(builder, text, style, startStyle, endStyle, css, attributes)
            }
            inner(builder, text.slice(0, part.to - start), style, startStyle, null, css, attributes);
            startStyle = null;
            text = text.slice(part.to - start);
            start = part.to;
        }
    }
}

function buildCollapsedSpan(builder, size, marker, ignoreWidget) {
    var widget = !ignoreWidget && marker.widgetNode;
    if (widget) {
        builder.map.push(builder.pos, builder.pos + size, widget);
    }
    if (!ignoreWidget && builder.cm.display.input.needsContentAttribute) {
        if (!widget) {
            widget = builder.content.appendChild(document.createElement("span"));
        }
        widget.setAttribute("cm-marker", marker.id);
    }
    if (widget) {
        builder.cm.display.input.setUneditable(widget);
        builder.content.appendChild(widget);
    }
    builder.pos += size;
    builder.trailingSpace = false;
}

// Outputs a number of spans to make up a line, taking highlighting
// and index text into account.
function insertLineContent(line, builder, styles) {
    var spans = line.markedSpans, allText = line.text, at = 0;
    if (!spans) {
        for (var i$1 = 1; i$1 < styles.length; i$1 += 2) {
            builder.addToken(builder, allText.slice(at, at = styles[i$1]), interpretTokenStyle(styles[i$1 + 1], builder.cm.options));
        }
        return
    }

    var len = allText.length, pos = 0, i = 1, text = "", style, css;
    var nextChange = 0, spanStyle, spanEndStyle, spanStartStyle, collapsed, attributes;
    for (; ;) {
        if (nextChange == pos) { // Update current marker set
            spanStyle = spanEndStyle = spanStartStyle = css = "";
            attributes = null;
            collapsed = null;
            nextChange = Infinity;
            var foundBookmarks = [], endStyles = (void 0);
            for (var j = 0; j < spans.length; ++j) {
                var sp = spans[j], m = sp.marker;
                if (m.type == "bookmark" && sp.from == pos && m.widgetNode) {
                    foundBookmarks.push(m);
                } else if (sp.from <= pos && (sp.to == null || sp.to > pos || m.collapsed && sp.to == pos && sp.from == pos)) {
                    if (sp.to != null && sp.to != pos && nextChange > sp.to) {
                        nextChange = sp.to;
                        spanEndStyle = "";
                    }
                    if (m.className) {
                        spanStyle += " " + m.className;
                    }
                    if (m.css) {
                        css = (css ? css + ";" : "") + m.css;
                    }
                    if (m.startStyle && sp.from == pos) {
                        spanStartStyle += " " + m.startStyle;
                    }
                    if (m.endStyle && sp.to == nextChange) {
                        (endStyles || (endStyles = [])).push(m.endStyle, sp.to);
                    }
                    // support for the old title property
                    // https://github.com/codemirror/CodeMirror/pull/5673
                    if (m.title) {
                        (attributes || (attributes = {})).title = m.title;
                    }
                    if (m.attributes) {
                        for (var attr in m.attributes) {
                            (attributes || (attributes = {}))[attr] = m.attributes[attr];
                        }
                    }
                    if (m.collapsed && (!collapsed || compareCollapsedMarkers(collapsed.marker, m) < 0)) {
                        collapsed = sp;
                    }
                } else if (sp.from > pos && nextChange > sp.from) {
                    nextChange = sp.from;
                }
            }
            if (endStyles) {
                for (var j$1 = 0; j$1 < endStyles.length; j$1 += 2) {
                    if (endStyles[j$1 + 1] == nextChange) {
                        spanEndStyle += " " + endStyles[j$1];
                    }
                }
            }

            if (!collapsed || collapsed.from == pos) {
                for (var j$2 = 0; j$2 < foundBookmarks.length; ++j$2) {
                    buildCollapsedSpan(builder, 0, foundBookmarks[j$2]);
                }
            }
            if (collapsed && (collapsed.from || 0) == pos) {
                buildCollapsedSpan(builder, (collapsed.to == null ? len + 1 : collapsed.to) - pos,
                    collapsed.marker, collapsed.from == null);
                if (collapsed.to == null) {
                    return
                }
                if (collapsed.to == pos) {
                    collapsed = false;
                }
            }
        }
        if (pos >= len) {
            break
        }

        var upto = Math.min(len, nextChange);
        while (true) {
            if (text) {
                var end = pos + text.length;
                if (!collapsed) {
                    var tokenText = end > upto ? text.slice(0, upto - pos) : text;
                    builder.addToken(builder, tokenText, style ? style + spanStyle : spanStyle,
                        spanStartStyle, pos + tokenText.length == nextChange ? spanEndStyle : "", css, attributes);
                }
                if (end >= upto) {
                    text = text.slice(upto - pos);
                    pos = upto;
                    break
                }
                pos = end;
                spanStartStyle = "";
            }
            text = allText.slice(at, at = styles[i++]);
            style = interpretTokenStyle(styles[i++], builder.cm.options);
        }
    }
}


// These objects are used to represent the visible (currently drawn)
// part of the document. A LineView may correspond to multiple
// logical lines, if those are connected by collapsed ranges.
function LineView(doc, line, lineN) {
    // The starting line
    this.line = line;
    // Continuing lines, if any
    this.rest = visualLineContinued(line);
    // Number of logical lines in this visual line
    this.size = this.rest ? lineNo(lst(this.rest)) - lineN + 1 : 1;
    this.node = this.text = null;
    this.hidden = lineIsHidden(doc, line);
}

// Create a range of LineView objects for the given lines.
function buildViewArray(cm, from, to) {
    var array = [], nextPos;
    for (var pos = from; pos < to; pos = nextPos) {
        var view = new LineView(cm.doc, getLine(cm.doc, pos), pos);
        nextPos = pos + view.size;
        array.push(view);
    }
    return array
}

var operationGroup = null;

function pushOperation(op) {
    if (operationGroup) {
        operationGroup.ops.push(op);
    } else {
        op.ownsGroup = operationGroup = {
            ops: [op],
            delayedCallbacks: []
        };
    }
}

function fireCallbacksForOps(group) {
    // Calls delayed callbacks and cursorActivity handlers until no
    // new ones appear
    var callbacks = group.delayedCallbacks, i = 0;
    do {
        for (; i < callbacks.length; i++) {
            callbacks[i].call(null);
        }
        for (var j = 0; j < group.ops.length; j++) {
            var op = group.ops[j];
            if (op.cursorActivityHandlers) {
                while (op.cursorActivityCalled < op.cursorActivityHandlers.length) {
                    op.cursorActivityHandlers[op.cursorActivityCalled++].call(null, op.cm);
                }
            }
        }
    } while (i < callbacks.length)
}

function finishOperation(op, endCb) {
    var group = op.ownsGroup;
    if (!group) {
        return
    }

    try {
        fireCallbacksForOps(group);
    } finally {
        operationGroup = null;
        endCb(group);
    }
}

var orphanDelayedCallbacks = null;

// Often, we want to signal events at a point where we are in the
// middle of some work, but don't want the handler to start calling
// other methods on the src, which might be in an inconsistent
// state or simply not expect any other events to happen.
// signalLater looks whether there are any handlers, and schedules
// them to be executed when the last operation ends, or, if no
// operation is active, when a timeout fires.
function signalLater(emitter, type /*, values...*/) {
    var arr = getHandlers(emitter, type);
    if (!arr.length) {
        return
    }
    var args = Array.prototype.slice.call(arguments, 2), list;
    if (operationGroup) {
        list = operationGroup.delayedCallbacks;
    } else if (orphanDelayedCallbacks) {
        list = orphanDelayedCallbacks;
    } else {
        list = orphanDelayedCallbacks = [];
        setTimeout(fireOrphanDelayed, 0);
    }
    var loop = function (i) {
        list.push(function () {
            return arr[i].apply(null, args);
        });
    };

    for (var i = 0; i < arr.length; ++i)
        loop(i);
}

function fireOrphanDelayed() {
    var delayed = orphanDelayedCallbacks;
    orphanDelayedCallbacks = null;
    for (var i = 0; i < delayed.length; ++i) {
        delayed[i]();
    }
}

// When an aspect of a line changes, a string is added to
// lineView.changes. This updates the relevant part of the line's
// DOM structure.
function updateLineForChanges(cm, lineView, lineN, dims) {
    for (var j = 0; j < lineView.changes.length; j++) {
        var type = lineView.changes[j];
        if (type == "text") {
            updateLineText(cm, lineView);
        } else if (type == "gutter") {
            updateLineGutter(cm, lineView, lineN, dims);
        } else if (type == "class") {
            updateLineClasses(cm, lineView);
        } else if (type == "widget") {
            updateLineWidgets(cm, lineView, dims);
        }
    }
    lineView.changes = null;
}

// Lines with gutter elements, widgets or a background class need to
// be wrapped, and have the extra elements added to the wrapper div
function ensureLineWrapped(lineView) {
    if (lineView.node == lineView.text) {
        lineView.node = elt("div", null, null, "position: relative");
        if (lineView.text.parentNode) {
            lineView.text.parentNode.replaceChild(lineView.node, lineView.text);
        }
        lineView.node.appendChild(lineView.text);
        if (ie && ie_version < 8) {
            lineView.node.style.zIndex = 2;
        }
    }
    return lineView.node
}

function updateLineBackground(cm, lineView) {
    var cls = lineView.bgClass ? lineView.bgClass + " " + (lineView.line.bgClass || "") : lineView.line.bgClass;
    if (cls) {
        cls += " CodeMirror-linebackground";
    }
    if (lineView.background) {
        if (cls) {
            lineView.background.className = cls;
        } else {
            lineView.background.parentNode.removeChild(lineView.background);
            lineView.background = null;
        }
    } else if (cls) {
        var wrap = ensureLineWrapped(lineView);
        lineView.background = wrap.insertBefore(elt("div", null, cls), wrap.firstChild);
        cm.display.input.setUneditable(lineView.background);
    }
}

// Wrapper around buildLineContent which will reuse the structure
// in display.externalMeasured when possible.
function getLineContent(cm, lineView) {
    var ext = cm.display.externalMeasured;
    if (ext && ext.line == lineView.line) {
        cm.display.externalMeasured = null;
        lineView.measure = ext.measure;
        return ext.built
    }
    return buildLineContent(cm, lineView)
}

// Redraw the line's text. Interacts with the background and text
// classes because the mode may output tokens that influence these
// classes.
function updateLineText(cm, lineView) {
    var cls = lineView.text.className;
    var built = getLineContent(cm, lineView);
    if (lineView.text == lineView.node) {
        lineView.node = built.pre;
    }
    lineView.text.parentNode.replaceChild(built.pre, lineView.text);
    lineView.text = built.pre;
    if (built.bgClass != lineView.bgClass || built.textClass != lineView.textClass) {
        lineView.bgClass = built.bgClass;
        lineView.textClass = built.textClass;
        updateLineClasses(cm, lineView);
    } else if (cls) {
        lineView.text.className = cls;
    }
}

function updateLineClasses(cm, lineView) {
    updateLineBackground(cm, lineView);
    if (lineView.line.wrapClass) {
        ensureLineWrapped(lineView).className = lineView.line.wrapClass;
    } else if (lineView.node != lineView.text) {
        lineView.node.className = "";
    }
    var textClass = lineView.textClass ? lineView.textClass + " " + (lineView.line.textClass || "") : lineView.line.textClass;
    lineView.text.className = textClass || "";
}

function updateLineGutter(cm, lineView, lineN, dims) {
    if (lineView.gutter) {
        lineView.node.removeChild(lineView.gutter);
        lineView.gutter = null;
    }
    if (lineView.gutterBackground) {
        lineView.node.removeChild(lineView.gutterBackground);
        lineView.gutterBackground = null;
    }
    if (lineView.line.gutterClass) {
        var wrap = ensureLineWrapped(lineView);
        lineView.gutterBackground = elt("div", null, "CodeMirror-gutter-background " + lineView.line.gutterClass,
            ("left: " + (cm.options.fixedGutter ? dims.fixedPos : -dims.gutterTotalWidth) + "px; width: " + (dims.gutterTotalWidth) + "px"));
        cm.display.input.setUneditable(lineView.gutterBackground);
        wrap.insertBefore(lineView.gutterBackground, lineView.text);
    }
    var markers = lineView.line.gutterMarkers;
    if (cm.options.lineNumbers || markers) {
        var wrap$1 = ensureLineWrapped(lineView);
        var gutterWrap = lineView.gutter = elt("div", null, "CodeMirror-gutter-wrapper", ("left: " + (cm.options.fixedGutter ? dims.fixedPos : -dims.gutterTotalWidth) + "px"));
        cm.display.input.setUneditable(gutterWrap);
        wrap$1.insertBefore(gutterWrap, lineView.text);
        if (lineView.line.gutterClass) {
            gutterWrap.className += " " + lineView.line.gutterClass;
        }
        if (cm.options.lineNumbers && (!markers || !markers["CodeMirror-linenumbers"])) {
            lineView.lineNumber = gutterWrap.appendChild(
                elt("div", lineNumberFor(cm.options, lineN),
                    "CodeMirror-linenumber CodeMirror-gutter-elt",
                    ("left: " + (dims.gutterLeft["CodeMirror-linenumbers"]) + "px; width: " + (cm.display.lineNumInnerWidth) + "px")));
        }
        if (markers) {
            for (var k = 0; k < cm.display.gutterSpecs.length; ++k) {
                var id = cm.display.gutterSpecs[k].className, found = markers.hasOwnProperty(id) && markers[id];
                if (found) {
                    gutterWrap.appendChild(elt("div", [found], "CodeMirror-gutter-elt",
                        ("left: " + (dims.gutterLeft[id]) + "px; width: " + (dims.gutterWidth[id]) + "px")));
                }
            }
        }
    }
}

function updateLineWidgets(cm, lineView, dims) {
    if (lineView.alignable) {
        lineView.alignable = null;
    }
    for (var node = lineView.node.firstChild, next = (void 0); node; node = next) {
        next = node.nextSibling;
        if (node.className == "CodeMirror-linewidget") {
            lineView.node.removeChild(node);
        }
    }
    insertLineWidgets(cm, lineView, dims);
}

// Build a line's DOM representation from scratch
function buildLineElement(cm, lineView, lineN, dims) {
    var built = getLineContent(cm, lineView);
    lineView.text = lineView.node = built.pre;
    if (built.bgClass) {
        lineView.bgClass = built.bgClass;
    }
    if (built.textClass) {
        lineView.textClass = built.textClass;
    }

    updateLineClasses(cm, lineView);
    updateLineGutter(cm, lineView, lineN, dims);
    insertLineWidgets(cm, lineView, dims);
    return lineView.node
}

// A lineView may contain multiple logical lines (when merged by
// collapsed spans). The widgets for all of them need to be drawn.
function insertLineWidgets(cm, lineView, dims) {
    insertLineWidgetsFor(cm, lineView.line, lineView, dims, true);
    if (lineView.rest) {
        for (var i = 0; i < lineView.rest.length; i++) {
            insertLineWidgetsFor(cm, lineView.rest[i], lineView, dims, false);
        }
    }
}

function insertLineWidgetsFor(cm, line, lineView, dims, allowAbove) {
    if (!line.widgets) {
        return
    }
    var wrap = ensureLineWrapped(lineView);
    for (var i = 0, ws = line.widgets; i < ws.length; ++i) {
        var widget = ws[i], node = elt("div", [widget.node], "CodeMirror-linewidget");
        if (!widget.handleMouseEvents) {
            node.setAttribute("cm-ignore-events", "true");
        }
        positionLineWidget(widget, node, lineView, dims);
        cm.display.input.setUneditable(node);
        if (allowAbove && widget.above) {
            wrap.insertBefore(node, lineView.gutter || lineView.text);
        } else {
            wrap.appendChild(node);
        }
        signalLater(widget, "redraw");
    }
}

function positionLineWidget(widget, node, lineView, dims) {
    if (widget.noHScroll) {
        (lineView.alignable || (lineView.alignable = [])).push(node);
        var width = dims.wrapperWidth;
        node.style.left = dims.fixedPos + "px";
        if (!widget.coverGutter) {
            width -= dims.gutterTotalWidth;
            node.style.paddingLeft = dims.gutterTotalWidth + "px";
        }
        node.style.width = width + "px";
    }
    if (widget.coverGutter) {
        node.style.zIndex = 5;
        node.style.position = "relative";
        if (!widget.noHScroll) {
            node.style.marginLeft = -dims.gutterTotalWidth + "px";
        }
    }
}

function widgetHeight(widget) {
    if (widget.height != null) {
        return widget.height
    }
    var cm = widget.doc.cm;
    if (!cm) {
        return 0
    }
    if (!contains(document.body, widget.node)) {
        var parentStyle = "position: relative;";
        if (widget.coverGutter) {
            parentStyle += "margin-left: -" + cm.display.gutters.offsetWidth + "px;";
        }
        if (widget.noHScroll) {
            parentStyle += "width: " + cm.display.wrapper.clientWidth + "px;";
        }
        removeChildrenAndAdd(cm.display.measure, elt("div", [widget.node], null, parentStyle));
    }
    return widget.height = widget.node.parentNode.offsetHeight
}

// Return true when the given mouse event happened in a widget
function eventInWidget(display, e) {
    for (var n = e_target(e); n != display.wrapper; n = n.parentNode) {
        if (!n || (n.nodeType == 1 && n.getAttribute("cm-ignore-events") == "true") ||
            (n.parentNode == display.sizer && n != display.mover)) {
            return true
        }
    }
}

// POSITION MEASUREMENT

function paddingTop(display) {
    return display.lineSpace.offsetTop
}

function paddingVert(display) {
    return display.mover.offsetHeight - display.lineSpace.offsetHeight
}

function paddingH(display) {
    if (display.cachedPaddingH) {
        return display.cachedPaddingH
    }
    var e = removeChildrenAndAdd(display.measure, elt("pre", "x", "CodeMirror-line-like"));
    var style = window.getComputedStyle ? window.getComputedStyle(e) : e.currentStyle;
    var data = {left: parseInt(style.paddingLeft), right: parseInt(style.paddingRight)};
    if (!isNaN(data.left) && !isNaN(data.right)) {
        display.cachedPaddingH = data;
    }
    return data
}

function scrollGap(cm) {
    return scrollerGap - cm.display.nativeBarWidth
}

function displayWidth(cm) {
    return cm.display.scroller.clientWidth - scrollGap(cm) - cm.display.barWidth
}

function displayHeight(cm) {
    return cm.display.scroller.clientHeight - scrollGap(cm) - cm.display.barHeight
}

// Ensure the lineView.wrapping.heights array is populated. This is
// an array of bottom offsets for the lines that make up a drawn
// line. When lineWrapping is on, there might be more than one
// height.
function ensureLineHeights(cm, lineView, rect) {
    var wrapping = cm.options.lineWrapping;
    var curWidth = wrapping && displayWidth(cm);
    if (!lineView.measure.heights || wrapping && lineView.measure.width != curWidth) {
        var heights = lineView.measure.heights = [];
        if (wrapping) {
            lineView.measure.width = curWidth;
            var rects = lineView.text.firstChild.getClientRects();
            for (var i = 0; i < rects.length - 1; i++) {
                var cur = rects[i], next = rects[i + 1];
                if (Math.abs(cur.bottom - next.bottom) > 2) {
                    heights.push((cur.bottom + next.top) / 2 - rect.top);
                }
            }
        }
        heights.push(rect.bottom - rect.top);
    }
}

// Find a line map (mapping character offsets to text nodes) and a
// measurement cache for the given line number. (A line view might
// contain multiple lines when collapsed ranges are present.)
function mapFromLineView(lineView, line, lineN) {
    if (lineView.line == line) {
        return {map: lineView.measure.map, cache: lineView.measure.cache}
    }
    for (var i = 0; i < lineView.rest.length; i++) {
        if (lineView.rest[i] == line) {
            return {map: lineView.measure.maps[i], cache: lineView.measure.caches[i]}
        }
    }
    for (var i$1 = 0; i$1 < lineView.rest.length; i$1++) {
        if (lineNo(lineView.rest[i$1]) > lineN) {
            return {map: lineView.measure.maps[i$1], cache: lineView.measure.caches[i$1], before: true}
        }
    }
}

// Render a line into the hidden node display.externalMeasured. Used
// when measurement is needed for a line that's not in the viewport.
function updateExternalMeasurement(cm, line) {
    line = visualLine(line);
    var lineN = lineNo(line);
    var view = cm.display.externalMeasured = new LineView(cm.doc, line, lineN);
    view.lineN = lineN;
    var built = view.built = buildLineContent(cm, view);
    view.text = built.pre;
    removeChildrenAndAdd(cm.display.lineMeasure, built.pre);
    return view
}

// Get a {top, bottom, left, right} box (in line-local coordinates)
// for a given character.
function measureChar(cm, line, ch, bias) {
    return measureCharPrepared(cm, prepareMeasureForLine(cm, line), ch, bias)
}

// Find a line view that corresponds to the given line number.
function findViewForLine(cm, lineN) {
    if (lineN >= cm.display.viewFrom && lineN < cm.display.viewTo) {
        return cm.display.view[findViewIndex(cm, lineN)]
    }
    var ext = cm.display.externalMeasured;
    if (ext && lineN >= ext.lineN && lineN < ext.lineN + ext.size) {
        return ext
    }
}

// Measurement can be split in two steps, the set-up work that
// applies to the whole line, and the measurement of the actual
// character. Functions like coordsChar, that need to do a lot of
// measurements in a row, can thus ensure that the set-up work is
// only done once.
function prepareMeasureForLine(cm, line) {
    var lineN = lineNo(line);
    var view = findViewForLine(cm, lineN);
    if (view && !view.text) {
        view = null;
    } else if (view && view.changes) {
        updateLineForChanges(cm, view, lineN, getDimensions(cm));
        cm.curOp.forceUpdate = true;
    }
    if (!view) {
        view = updateExternalMeasurement(cm, line);
    }

    var info = mapFromLineView(view, line, lineN);
    return {
        line: line, view: view, rect: null,
        map: info.map, cache: info.cache, before: info.before,
        hasHeights: false
    }
}

// Given a prepared measurement object, measures the position of an
// actual character (or fetches it from the cache).
function measureCharPrepared(cm, prepared, ch, bias, varHeight) {
    if (prepared.before) {
        ch = -1;
    }
    var key = ch + (bias || ""), found;
    if (prepared.cache.hasOwnProperty(key)) {
        found = prepared.cache[key];
    } else {
        if (!prepared.rect) {
            prepared.rect = prepared.view.text.getBoundingClientRect();
        }
        if (!prepared.hasHeights) {
            ensureLineHeights(cm, prepared.view, prepared.rect);
            prepared.hasHeights = true;
        }
        found = measureCharInner(cm, prepared, ch, bias);
        if (!found.bogus) {
            prepared.cache[key] = found;
        }
    }
    return {
        left: found.left, right: found.right,
        top: varHeight ? found.rtop : found.top,
        bottom: varHeight ? found.rbottom : found.bottom
    }
}

var nullRect = {left: 0, right: 0, top: 0, bottom: 0};

function nodeAndOffsetInLineMap(map$$1, ch, bias) {
    var node, start, end, collapse, mStart, mEnd;
    // First, search the line map for the text node corresponding to,
    // or closest to, the target character.
    for (var i = 0; i < map$$1.length; i += 3) {
        mStart = map$$1[i];
        mEnd = map$$1[i + 1];
        if (ch < mStart) {
            start = 0;
            end = 1;
            collapse = "left";
        } else if (ch < mEnd) {
            start = ch - mStart;
            end = start + 1;
        } else if (i == map$$1.length - 3 || ch == mEnd && map$$1[i + 3] > ch) {
            end = mEnd - mStart;
            start = end - 1;
            if (ch >= mEnd) {
                collapse = "right";
            }
        }
        if (start != null) {
            node = map$$1[i + 2];
            if (mStart == mEnd && bias == (node.insertLeft ? "left" : "right")) {
                collapse = bias;
            }
            if (bias == "left" && start == 0) {
                while (i && map$$1[i - 2] == map$$1[i - 3] && map$$1[i - 1].insertLeft) {
                    node = map$$1[(i -= 3) + 2];
                    collapse = "left";
                }
            }
            if (bias == "right" && start == mEnd - mStart) {
                while (i < map$$1.length - 3 && map$$1[i + 3] == map$$1[i + 4] && !map$$1[i + 5].insertLeft) {
                    node = map$$1[(i += 3) + 2];
                    collapse = "right";
                }
            }
            break
        }
    }
    return {node: node, start: start, end: end, collapse: collapse, coverStart: mStart, coverEnd: mEnd}
}

function getUsefulRect(rects, bias) {
    var rect = nullRect;
    if (bias == "left") {
        for (var i = 0; i < rects.length; i++) {
            if ((rect = rects[i]).left != rect.right) {
                break
            }
        }
    } else {
        for (var i$1 = rects.length - 1; i$1 >= 0; i$1--) {
            if ((rect = rects[i$1]).left != rect.right) {
                break
            }
        }
    }
    return rect
}

function measureCharInner(cm, prepared, ch, bias) {
    var place = nodeAndOffsetInLineMap(prepared.map, ch, bias);
    var node = place.node, start = place.start, end = place.end, collapse = place.collapse;

    var rect;
    if (node.nodeType == 3) { // If it is a text node, use a range to retrieve the coordinates.
        for (var i$1 = 0; i$1 < 4; i$1++) { // Retry a maximum of 4 times when nonsense rectangles are returned
            while (start && isExtendingChar(prepared.line.text.charAt(place.coverStart + start))) {
                --start;
            }
            while (place.coverStart + end < place.coverEnd && isExtendingChar(prepared.line.text.charAt(place.coverStart + end))) {
                ++end;
            }
            if (ie && ie_version < 9 && start == 0 && end == place.coverEnd - place.coverStart) {
                rect = node.parentNode.getBoundingClientRect();
            } else {
                rect = getUsefulRect(range(node, start, end).getClientRects(), bias);
            }
            if (rect.left || rect.right || start == 0) {
                break
            }
            end = start;
            start = start - 1;
            collapse = "right";
        }
        if (ie && ie_version < 11) {
            rect = maybeUpdateRectForZooming(cm.display.measure, rect);
        }
    } else { // If it is a widget, simply get the box for the whole widget.
        if (start > 0) {
            collapse = bias = "right";
        }
        var rects;
        if (cm.options.lineWrapping && (rects = node.getClientRects()).length > 1) {
            rect = rects[bias == "right" ? rects.length - 1 : 0];
        } else {
            rect = node.getBoundingClientRect();
        }
    }
    if (ie && ie_version < 9 && !start && (!rect || !rect.left && !rect.right)) {
        var rSpan = node.parentNode.getClientRects()[0];
        if (rSpan) {
            rect = {left: rSpan.left, right: rSpan.left + charWidth(cm.display), top: rSpan.top, bottom: rSpan.bottom};
        } else {
            rect = nullRect;
        }
    }

    var rtop = rect.top - prepared.rect.top, rbot = rect.bottom - prepared.rect.top;
    var mid = (rtop + rbot) / 2;
    var heights = prepared.view.measure.heights;
    var i = 0;
    for (; i < heights.length - 1; i++) {
        if (mid < heights[i]) {
            break
        }
    }
    var top = i ? heights[i - 1] : 0, bot = heights[i];
    var result = {
        left: (collapse == "right" ? rect.right : rect.left) - prepared.rect.left,
        right: (collapse == "left" ? rect.left : rect.right) - prepared.rect.left,
        top: top, bottom: bot
    };
    if (!rect.left && !rect.right) {
        result.bogus = true;
    }
    if (!cm.options.singleCursorHeightPerLine) {
        result.rtop = rtop;
        result.rbottom = rbot;
    }

    return result
}

// Work around problem with bounding client rects on ranges being
// returned incorrectly when zoomed on IE10 and below.
function maybeUpdateRectForZooming(measure, rect) {
    if (!window.screen || screen.logicalXDPI == null ||
        screen.logicalXDPI == screen.deviceXDPI || !hasBadZoomedRects(measure)) {
        return rect
    }
    var scaleX = screen.logicalXDPI / screen.deviceXDPI;
    var scaleY = screen.logicalYDPI / screen.deviceYDPI;
    return {
        left: rect.left * scaleX, right: rect.right * scaleX,
        top: rect.top * scaleY, bottom: rect.bottom * scaleY
    }
}

function clearLineMeasurementCacheFor(lineView) {
    if (lineView.measure) {
        lineView.measure.cache = {};
        lineView.measure.heights = null;
        if (lineView.rest) {
            for (var i = 0; i < lineView.rest.length; i++) {
                lineView.measure.caches[i] = {};
            }
        }
    }
}

function clearLineMeasurementCache(cm) {
    cm.display.externalMeasure = null;
    removeChildren(cm.display.lineMeasure);
    for (var i = 0; i < cm.display.view.length; i++) {
        clearLineMeasurementCacheFor(cm.display.view[i]);
    }
}

function clearCaches(cm) {
    clearLineMeasurementCache(cm);
    cm.display.cachedCharWidth = cm.display.cachedTextHeight = cm.display.cachedPaddingH = null;
    if (!cm.options.lineWrapping) {
        cm.display.maxLineChanged = true;
    }
    cm.display.lineNumChars = null;
}

function pageScrollX() {
    // Work around https://bugs.chromium.org/p/chromium/issues/detail?id=489206
    // which causes page_Offset and bounding client rects to use
    // different reference viewports and invalidate our calculations.
    if (chrome && android) {
        return -(document.body.getBoundingClientRect().left - parseInt(getComputedStyle(document.body).marginLeft))
    }
    return window.pageXOffset || (document.documentElement || document.body).scrollLeft
}

function pageScrollY() {
    if (chrome && android) {
        return -(document.body.getBoundingClientRect().top - parseInt(getComputedStyle(document.body).marginTop))
    }
    return window.pageYOffset || (document.documentElement || document.body).scrollTop
}

function widgetTopHeight(lineObj) {
    var height = 0;
    if (lineObj.widgets) {
        for (var i = 0; i < lineObj.widgets.length; ++i) {
            if (lineObj.widgets[i].above) {
                height += widgetHeight(lineObj.widgets[i]);
            }
        }
    }
    return height
}

// Converts a {top, bottom, left, right} box from line-local
// coordinates into another coordinate system. Context may be one of
// "line", "div" (display.lineDiv), "local"./null (src), "window",
// or "page".
function intoCoordSystem(cm, lineObj, rect, context, includeWidgets) {
    if (!includeWidgets) {
        var height = widgetTopHeight(lineObj);
        rect.top += height;
        rect.bottom += height;
    }
    if (context == "line") {
        return rect
    }
    if (!context) {
        context = "local";
    }
    var yOff = heightAtLine(lineObj);
    if (context == "local") {
        yOff += paddingTop(cm.display);
    } else {
        yOff -= cm.display.viewOffset;
    }
    if (context == "page" || context == "window") {
        var lOff = cm.display.lineSpace.getBoundingClientRect();
        yOff += lOff.top + (context == "window" ? 0 : pageScrollY());
        var xOff = lOff.left + (context == "window" ? 0 : pageScrollX());
        rect.left += xOff;
        rect.right += xOff;
    }
    rect.top += yOff;
    rect.bottom += yOff;
    return rect
}

// Coverts a box from "div" coords to another coordinate system.
// Context may be "window", "page", "div", or "local"./null.
function fromCoordSystem(cm, coords, context) {
    if (context == "div") {
        return coords
    }
    var left = coords.left, top = coords.top;
    // First move into "page" coordinate system
    if (context == "page") {
        left -= pageScrollX();
        top -= pageScrollY();
    } else if (context == "local" || !context) {
        var localBox = cm.display.sizer.getBoundingClientRect();
        left += localBox.left;
        top += localBox.top;
    }

    var lineSpaceBox = cm.display.lineSpace.getBoundingClientRect();
    return {left: left - lineSpaceBox.left, top: top - lineSpaceBox.top}
}

function charCoords(cm, pos, context, lineObj, bias) {
    if (!lineObj) {
        lineObj = getLine(cm.doc, pos.line);
    }
    return intoCoordSystem(cm, lineObj, measureChar(cm, lineObj, pos.ch, bias), context)
}

// Returns a box for a given cursor position, which may have an
// 'other' property containing the position of the secondary cursor
// on a bidi boundary.
// A cursor Pos(line, char, "before") is on the same visual line as `char - 1`
// and after `char - 1` in writing order of `char - 1`
// A cursor Pos(line, char, "after") is on the same visual line as `char`
// and before `char` in writing order of `char`
// Examples (upper-case letters are RTL, lower-case are LTR):
//     Pos(0, 1, ...)
//     before   after
// ab     a|b     a|b
// aB     a|B     aB|
// Ab     |Ab     A|b
// AB     B|A     B|A
// Every position after the last character on a line is considered to stick
// to the last character on the line.
function cursorCoords(cm, pos, context, lineObj, preparedMeasure, varHeight) {
    lineObj = lineObj || getLine(cm.doc, pos.line);
    if (!preparedMeasure) {
        preparedMeasure = prepareMeasureForLine(cm, lineObj);
    }

    function get(ch, right) {
        var m = measureCharPrepared(cm, preparedMeasure, ch, right ? "right" : "left", varHeight);
        if (right) {
            m.left = m.right;
        } else {
            m.right = m.left;
        }
        return intoCoordSystem(cm, lineObj, m, context)
    }

    var order = getOrder(lineObj, cm.doc.direction), ch = pos.ch, sticky = pos.sticky;
    if (ch >= lineObj.text.length) {
        ch = lineObj.text.length;
        sticky = "before";
    } else if (ch <= 0) {
        ch = 0;
        sticky = "after";
    }
    if (!order) {
        return get(sticky == "before" ? ch - 1 : ch, sticky == "before")
    }

    function getBidi(ch, partPos, invert) {
        var part = order[partPos], right = part.level == 1;
        return get(invert ? ch - 1 : ch, right != invert)
    }

    var partPos = getBidiPartAt(order, ch, sticky);
    var other = bidiOther;
    var val = getBidi(ch, partPos, sticky == "before");
    if (other != null) {
        val.other = getBidi(ch, other, sticky != "before");
    }
    return val
}

// Used to cheaply estimate the coordinates for a position. Used for
// intermediate scroll updates.
function estimateCoords(cm, pos) {
    var left = 0;
    pos = clipPos(cm.doc, pos);
    if (!cm.options.lineWrapping) {
        left = charWidth(cm.display) * pos.ch;
    }
    var lineObj = getLine(cm.doc, pos.line);
    var top = heightAtLine(lineObj) + paddingTop(cm.display);
    return {left: left, right: left, top: top, bottom: top + lineObj.height}
}

// Positions returned by coordsChar contain some extra information.
// xRel is the relative x position of the input coordinates compared
// to the found position (so xRel > 0 means the coordinates are to
// the right of the character position, for example). When outside
// is true, that means the coordinates lie outside the line's
// vertical range.
function PosWithInfo(line, ch, sticky, outside, xRel) {
    var pos = Pos(line, ch, sticky);
    pos.xRel = xRel;
    if (outside) {
        pos.outside = outside;
    }
    return pos
}

// Compute the character position closest to the given coordinates.
// Input must be lineSpace-local ("div" coordinate system).
function coordsChar(cm, x, y) {
    var doc = cm.doc;
    y += cm.display.viewOffset;
    if (y < 0) {
        return PosWithInfo(doc.first, 0, null, -1, -1)
    }
    var lineN = lineAtHeight(doc, y), last = doc.first + doc.size - 1;
    if (lineN > last) {
        return PosWithInfo(doc.first + doc.size - 1, getLine(doc, last).text.length, null, 1, 1)
    }
    if (x < 0) {
        x = 0;
    }

    var lineObj = getLine(doc, lineN);
    for (; ;) {
        var found = coordsCharInner(cm, lineObj, lineN, x, y);
        var collapsed = collapsedSpanAround(lineObj, found.ch + (found.xRel > 0 || found.outside > 0 ? 1 : 0));
        if (!collapsed) {
            return found
        }
        var rangeEnd = collapsed.find(1);
        if (rangeEnd.line == lineN) {
            return rangeEnd
        }
        lineObj = getLine(doc, lineN = rangeEnd.line);
    }
}

function wrappedLineExtent(cm, lineObj, preparedMeasure, y) {
    y -= widgetTopHeight(lineObj);
    var end = lineObj.text.length;
    var begin = findFirst(function (ch) {
        return measureCharPrepared(cm, preparedMeasure, ch - 1).bottom <= y;
    }, end, 0);
    end = findFirst(function (ch) {
        return measureCharPrepared(cm, preparedMeasure, ch).top > y;
    }, begin, end);
    return {begin: begin, end: end}
}

function wrappedLineExtentChar(cm, lineObj, preparedMeasure, target) {
    if (!preparedMeasure) {
        preparedMeasure = prepareMeasureForLine(cm, lineObj);
    }
    var targetTop = intoCoordSystem(cm, lineObj, measureCharPrepared(cm, preparedMeasure, target), "line").top;
    return wrappedLineExtent(cm, lineObj, preparedMeasure, targetTop)
}

// Returns true if the given side of a box is after the given
// coordinates, in top-to-bottom, left-to-right order.
function boxIsAfter(box, x, y, left) {
    return box.bottom <= y ? false : box.top > y ? true : (left ? box.left : box.right) > x
}

function coordsCharInner(cm, lineObj, lineNo$$1, x, y) {
    // Move y into line-local coordinate space
    y -= heightAtLine(lineObj);
    var preparedMeasure = prepareMeasureForLine(cm, lineObj);
    // When directly calling `measureCharPrepared`, we have to adjust
    // for the widgets at this line.
    var widgetHeight$$1 = widgetTopHeight(lineObj);
    var begin = 0, end = lineObj.text.length, ltr = true;

    var order = getOrder(lineObj, cm.doc.direction);
    // If the line isn't plain left-to-right text, first figure out
    // which bidi section the coordinates fall into.
    if (order) {
        var part = (cm.options.lineWrapping ? coordsBidiPartWrapped : coordsBidiPart)
        (cm, lineObj, lineNo$$1, preparedMeasure, order, x, y);
        ltr = part.level != 1;
        // The awkward -1 offsets are needed because findFirst (called
        // on these below) will treat its first bound as inclusive,
        // second as exclusive, but we want to actually address the
        // characters in the part's range
        begin = ltr ? part.from : part.to - 1;
        end = ltr ? part.to : part.from - 1;
    }

    // A binary search to find the first character whose bounding box
    // starts after the coordinates. If we run across any whose box wrap
    // the coordinates, store that.
    var chAround = null, boxAround = null;
    var ch = findFirst(function (ch) {
        var box = measureCharPrepared(cm, preparedMeasure, ch);
        box.top += widgetHeight$$1;
        box.bottom += widgetHeight$$1;
        if (!boxIsAfter(box, x, y, false)) {
            return false
        }
        if (box.top <= y && box.left <= x) {
            chAround = ch;
            boxAround = box;
        }
        return true
    }, begin, end);

    var baseX, sticky, outside = false;
    // If a box around the coordinates was found, use that
    if (boxAround) {
        // Distinguish coordinates nearer to the left or right side of the box
        var atLeft = x - boxAround.left < boxAround.right - x, atStart = atLeft == ltr;
        ch = chAround + (atStart ? 0 : 1);
        sticky = atStart ? "after" : "before";
        baseX = atLeft ? boxAround.left : boxAround.right;
    } else {
        // (Adjust for extended bound, if necessary.)
        if (!ltr && (ch == end || ch == begin)) {
            ch++;
        }
        // To determine which side to associate with, get the box to the
        // left of the character and compare it's vertical position to the
        // coordinates
        sticky = ch == 0 ? "after" : ch == lineObj.text.length ? "before" :
            (measureCharPrepared(cm, preparedMeasure, ch - (ltr ? 1 : 0)).bottom + widgetHeight$$1 <= y) == ltr ?
                "after" : "before";
        // Now get accurate coordinates for this place, in order to get a
        // base X position
        var coords = cursorCoords(cm, Pos(lineNo$$1, ch, sticky), "line", lineObj, preparedMeasure);
        baseX = coords.left;
        outside = y < coords.top ? -1 : y >= coords.bottom ? 1 : 0;
    }

    ch = skipExtendingChars(lineObj.text, ch, 1);
    return PosWithInfo(lineNo$$1, ch, sticky, outside, x - baseX)
}

function coordsBidiPart(cm, lineObj, lineNo$$1, preparedMeasure, order, x, y) {
    // Bidi parts are sorted left-to-right, and in a non-line-wrapping
    // situation, we can take this ordering to correspond to the visual
    // ordering. This finds the first part whose end is after the given
    // coordinates.
    var index = findFirst(function (i) {
        var part = order[i], ltr = part.level != 1;
        return boxIsAfter(cursorCoords(cm, Pos(lineNo$$1, ltr ? part.to : part.from, ltr ? "before" : "after"),
            "line", lineObj, preparedMeasure), x, y, true)
    }, 0, order.length - 1);
    var part = order[index];
    // If this isn't the first part, the part's start is also after
    // the coordinates, and the coordinates aren't on the same line as
    // that start, move one part back.
    if (index > 0) {
        var ltr = part.level != 1;
        var start = cursorCoords(cm, Pos(lineNo$$1, ltr ? part.from : part.to, ltr ? "after" : "before"),
            "line", lineObj, preparedMeasure);
        if (boxIsAfter(start, x, y, true) && start.top > y) {
            part = order[index - 1];
        }
    }
    return part
}

function coordsBidiPartWrapped(cm, lineObj, _lineNo, preparedMeasure, order, x, y) {
    // In a wrapped line, rtl text on wrapping boundaries can do things
    // that don't correspond to the ordering in our `order` array at
    // all, so a binary search doesn't work, and we want to return a
    // part that only spans one line so that the binary search in
    // coordsCharInner is safe. As such, we first find the extent of the
    // wrapped line, and then do a flat search in which we discard any
    // spans that aren't on the line.
    var ref = wrappedLineExtent(cm, lineObj, preparedMeasure, y);
    var begin = ref.begin;
    var end = ref.end;
    if (/\s/.test(lineObj.text.charAt(end - 1))) {
        end--;
    }
    var part = null, closestDist = null;
    for (var i = 0; i < order.length; i++) {
        var p = order[i];
        if (p.from >= end || p.to <= begin) {
            continue
        }
        var ltr = p.level != 1;
        var endX = measureCharPrepared(cm, preparedMeasure, ltr ? Math.min(end, p.to) - 1 : Math.max(begin, p.from)).right;
        // Weigh against spans ending before this, so that they are only
        // picked if nothing ends after
        var dist = endX < x ? x - endX + 1e9 : endX - x;
        if (!part || closestDist > dist) {
            part = p;
            closestDist = dist;
        }
    }
    if (!part) {
        part = order[order.length - 1];
    }
    // Clip the part to the wrapped line.
    if (part.from < begin) {
        part = {from: begin, to: part.to, level: part.level};
    }
    if (part.to > end) {
        part = {from: part.from, to: end, level: part.level};
    }
    return part
}

var measureText;

// Compute the default text height.
function textHeight(display) {
    if (display.cachedTextHeight != null) {
        return display.cachedTextHeight
    }
    if (measureText == null) {
        measureText = elt("pre", null, "CodeMirror-line-like");
        // Measure a bunch of lines, for browsers that compute
        // fractional heights.
        for (var i = 0; i < 49; ++i) {
            measureText.appendChild(document.createTextNode("x"));
            measureText.appendChild(elt("br"));
        }
        measureText.appendChild(document.createTextNode("x"));
    }
    removeChildrenAndAdd(display.measure, measureText);
    var height = measureText.offsetHeight / 50;
    if (height > 3) {
        display.cachedTextHeight = height;
    }
    removeChildren(display.measure);
    return height || 1
}

// Compute the default character width.
function charWidth(display) {
    if (display.cachedCharWidth != null) {
        return display.cachedCharWidth
    }
    var anchor = elt("span", "xxxxxxxxxx");
    var pre = elt("pre", [anchor], "CodeMirror-line-like");
    removeChildrenAndAdd(display.measure, pre);
    var rect = anchor.getBoundingClientRect(), width = (rect.right - rect.left) / 10;
    if (width > 2) {
        display.cachedCharWidth = width;
    }
    return width || 10
}

// Do a bulk-read of the DOM positions and sizes needed to draw the
// view, so that we don't interleave reading and writing to the DOM.
function getDimensions(cm) {
    var d = cm.display, left = {}, width = {};
    var gutterLeft = d.gutters.clientLeft;
    for (var n = d.gutters.firstChild, i = 0; n; n = n.nextSibling, ++i) {
        var id = cm.display.gutterSpecs[i].className;
        left[id] = n.offsetLeft + n.clientLeft + gutterLeft;
        width[id] = n.clientWidth;
    }
    return {
        fixedPos: compensateForHScroll(d),
        gutterTotalWidth: d.gutters.offsetWidth,
        gutterLeft: left,
        gutterWidth: width,
        wrapperWidth: d.wrapper.clientWidth
    }
}

// Computes display.scroller.scrollLeft + display.gutters.offsetWidth,
// but using getBoundingClientRect to get a sub-pixel-accurate
// result.
function compensateForHScroll(display) {
    return display.scroller.getBoundingClientRect().left - display.sizer.getBoundingClientRect().left
}

// Returns a function that estimates the height of a line, to use as
// first approximation until the line becomes visible (and is thus
// properly measurable).
function estimateHeight(cm) {
    var th = textHeight(cm.display), wrapping = cm.options.lineWrapping;
    var perLine = wrapping && Math.max(5, cm.display.scroller.clientWidth / charWidth(cm.display) - 3);
    return function (line) {
        if (lineIsHidden(cm.doc, line)) {
            return 0
        }

        var widgetsHeight = 0;
        if (line.widgets) {
            for (var i = 0; i < line.widgets.length; i++) {
                if (line.widgets[i].height) {
                    widgetsHeight += line.widgets[i].height;
                }
            }
        }

        if (wrapping) {
            return widgetsHeight + (Math.ceil(line.text.length / perLine) || 1) * th
        } else {
            return widgetsHeight + th
        }
    }
}

function estimateLineHeights(cm) {
    var doc = cm.doc, est = estimateHeight(cm);
    doc.iter(function (line) {
        var estHeight = est(line);
        if (estHeight != line.height) {
            updateLineHeight(line, estHeight);
        }
    });
}

// Given a mouse event, find the corresponding position. If liberal
// is false, it checks whether a gutter or scrollbar was clicked,
// and returns null if it was. forRect is used by rectangular
// selections, and tries to estimate a character position even for
// coordinates beyond the right of the text.
function posFromMouse(cm, e, liberal, forRect) {
    var display = cm.display;
    if (!liberal && e_target(e).getAttribute("cm-not-content") == "true") {
        return null
    }

    var x, y, space = display.lineSpace.getBoundingClientRect();
    // Fails unpredictably on IE[67] when mouse is dragged around quickly.
    try {
        x = e.clientX - space.left;
        y = e.clientY - space.top;
    } catch (e) {
        return null
    }
    var coords = coordsChar(cm, x, y), line;
    if (forRect && coords.xRel == 1 && (line = getLine(cm.doc, coords.line).text).length == coords.ch) {
        var colDiff = countColumn(line, line.length, cm.options.tabSize) - line.length;
        coords = Pos(coords.line, Math.max(0, Math.round((x - paddingH(cm.display).left) / charWidth(cm.display)) - colDiff));
    }
    return coords
}

// Find the view element corresponding to a given line. Return null
// when the line isn't visible.
function findViewIndex(cm, n) {
    if (n >= cm.display.viewTo) {
        return null
    }
    n -= cm.display.viewFrom;
    if (n < 0) {
        return null
    }
    var view = cm.display.view;
    for (var i = 0; i < view.length; i++) {
        n -= view[i].size;
        if (n < 0) {
            return i
        }
    }
}

// Updates the display.view data structure for a given change to the
// document. From and to are in pre-change coordinates. Lendiff is
// the amount of lines added or subtracted by the change. This is
// used for changes that span multiple lines, or change the way
// lines are divided into visual lines. regLineChange (below)
// registers single-line changes.
function regChange(cm, from, to, lendiff) {
    if (from == null) {
        from = cm.doc.first;
    }
    if (to == null) {
        to = cm.doc.first + cm.doc.size;
    }
    if (!lendiff) {
        lendiff = 0;
    }

    var display = cm.display;
    if (lendiff && to < display.viewTo &&
        (display.updateLineNumbers == null || display.updateLineNumbers > from)) {
        display.updateLineNumbers = from;
    }

    cm.curOp.viewChanged = true;

    if (from >= display.viewTo) { // Change after
        if (sawCollapsedSpans && visualLineNo(cm.doc, from) < display.viewTo) {
            resetView(cm);
        }
    } else if (to <= display.viewFrom) { // Change before
        if (sawCollapsedSpans && visualLineEndNo(cm.doc, to + lendiff) > display.viewFrom) {
            resetView(cm);
        } else {
            display.viewFrom += lendiff;
            display.viewTo += lendiff;
        }
    } else if (from <= display.viewFrom && to >= display.viewTo) { // Full overlap
        resetView(cm);
    } else if (from <= display.viewFrom) { // Top overlap
        var cut = viewCuttingPoint(cm, to, to + lendiff, 1);
        if (cut) {
            display.view = display.view.slice(cut.index);
            display.viewFrom = cut.lineN;
            display.viewTo += lendiff;
        } else {
            resetView(cm);
        }
    } else if (to >= display.viewTo) { // Bottom overlap
        var cut$1 = viewCuttingPoint(cm, from, from, -1);
        if (cut$1) {
            display.view = display.view.slice(0, cut$1.index);
            display.viewTo = cut$1.lineN;
        } else {
            resetView(cm);
        }
    } else { // Gap in the middle
        var cutTop = viewCuttingPoint(cm, from, from, -1);
        var cutBot = viewCuttingPoint(cm, to, to + lendiff, 1);
        if (cutTop && cutBot) {
            display.view = display.view.slice(0, cutTop.index)
                .concat(buildViewArray(cm, cutTop.lineN, cutBot.lineN))
                .concat(display.view.slice(cutBot.index));
            display.viewTo += lendiff;
        } else {
            resetView(cm);
        }
    }

    var ext = display.externalMeasured;
    if (ext) {
        if (to < ext.lineN) {
            ext.lineN += lendiff;
        } else if (from < ext.lineN + ext.size) {
            display.externalMeasured = null;
        }
    }
}

// Register a change to a single line. Type must be one of "text",
// "gutter", "class", "widget"
function regLineChange(cm, line, type) {
    cm.curOp.viewChanged = true;
    var display = cm.display, ext = cm.display.externalMeasured;
    if (ext && line >= ext.lineN && line < ext.lineN + ext.size) {
        display.externalMeasured = null;
    }

    if (line < display.viewFrom || line >= display.viewTo) {
        return
    }
    var lineView = display.view[findViewIndex(cm, line)];
    if (lineView.node == null) {
        return
    }
    var arr = lineView.changes || (lineView.changes = []);
    if (indexOf(arr, type) == -1) {
        arr.push(type);
    }
}

// Clear the view.
function resetView(cm) {
    cm.display.viewFrom = cm.display.viewTo = cm.doc.first;
    cm.display.view = [];
    cm.display.viewOffset = 0;
}

function viewCuttingPoint(cm, oldN, newN, dir) {
    var index = findViewIndex(cm, oldN), diff, view = cm.display.view;
    if (!sawCollapsedSpans || newN == cm.doc.first + cm.doc.size) {
        return {index: index, lineN: newN}
    }
    var n = cm.display.viewFrom;
    for (var i = 0; i < index; i++) {
        n += view[i].size;
    }
    if (n != oldN) {
        if (dir > 0) {
            if (index == view.length - 1) {
                return null
            }
            diff = (n + view[index].size) - oldN;
            index++;
        } else {
            diff = n - oldN;
        }
        oldN += diff;
        newN += diff;
    }
    while (visualLineNo(cm.doc, newN) != newN) {
        if (index == (dir < 0 ? 0 : view.length - 1)) {
            return null
        }
        newN += dir * view[index - (dir < 0 ? 1 : 0)].size;
        index += dir;
    }
    return {index: index, lineN: newN}
}

// Force the view to cover a given range, adding empty view element
// or clipping off existing ones as needed.
function adjustView(cm, from, to) {
    var display = cm.display, view = display.view;
    if (view.length == 0 || from >= display.viewTo || to <= display.viewFrom) {
        display.view = buildViewArray(cm, from, to);
        display.viewFrom = from;
    } else {
        if (display.viewFrom > from) {
            display.view = buildViewArray(cm, from, display.viewFrom).concat(display.view);
        } else if (display.viewFrom < from) {
            display.view = display.view.slice(findViewIndex(cm, from));
        }
        display.viewFrom = from;
        if (display.viewTo < to) {
            display.view = display.view.concat(buildViewArray(cm, display.viewTo, to));
        } else if (display.viewTo > to) {
            display.view = display.view.slice(0, findViewIndex(cm, to));
        }
    }
    display.viewTo = to;
}

// Count the number of lines in the view whose DOM representation is
// out of date (or nonexistent).
function countDirtyView(cm) {
    var view = cm.display.view, dirty = 0;
    for (var i = 0; i < view.length; i++) {
        var lineView = view[i];
        if (!lineView.hidden && (!lineView.node || lineView.changes)) {
            ++dirty;
        }
    }
    return dirty
}

function updateSelection(cm) {
    cm.display.input.showSelection(cm.display.input.prepareSelection());
}

function prepareSelection(cm, primary) {
    if (primary === void 0) primary = true;

    var doc = cm.doc, result = {};
    var curFragment = result.cursors = document.createDocumentFragment();
    var selFragment = result.selection = document.createDocumentFragment();

    for (var i = 0; i < doc.sel.ranges.length; i++) {
        if (!primary && i == doc.sel.primIndex) {
            continue
        }
        var range$$1 = doc.sel.ranges[i];
        if (range$$1.from().line >= cm.display.viewTo || range$$1.to().line < cm.display.viewFrom) {
            continue
        }
        var collapsed = range$$1.empty();
        if (collapsed || cm.options.showCursorWhenSelecting) {
            drawSelectionCursor(cm, range$$1.head, curFragment);
        }
        if (!collapsed) {
            drawSelectionRange(cm, range$$1, selFragment);
        }
    }
    return result
}

// Draws a cursor for the given range
function drawSelectionCursor(cm, head, output) {
    var pos = cursorCoords(cm, head, "div", null, null, !cm.options.singleCursorHeightPerLine);

    var cursor = output.appendChild(elt("div", "\u00a0", "CodeMirror-cursor"));
    cursor.style.left = pos.left + "px";
    cursor.style.top = pos.top + "px";
    cursor.style.height = Math.max(0, pos.bottom - pos.top) * cm.options.cursorHeight + "px";

    if (pos.other) {
        // Secondary cursor, shown when on a 'jump' in bi-directional text
        var otherCursor = output.appendChild(elt("div", "\u00a0", "CodeMirror-cursor CodeMirror-secondarycursor"));
        otherCursor.style.display = "";
        otherCursor.style.left = pos.other.left + "px";
        otherCursor.style.top = pos.other.top + "px";
        otherCursor.style.height = (pos.other.bottom - pos.other.top) * .85 + "px";
    }
}

function cmpCoords(a, b) {
    return a.top - b.top || a.left - b.left
}

// Draws the given range as a highlighted selection
function drawSelectionRange(cm, range$$1, output) {
    var display = cm.display, doc = cm.doc;
    var fragment = document.createDocumentFragment();
    var padding = paddingH(cm.display), leftSide = padding.left;
    var rightSide = Math.max(display.sizerWidth, displayWidth(cm) - display.sizer.offsetLeft) - padding.right;
    var docLTR = doc.direction == "ltr";

    function add(left, top, width, bottom) {
        if (top < 0) {
            top = 0;
        }
        top = Math.round(top);
        bottom = Math.round(bottom);
        fragment.appendChild(elt("div", null, "CodeMirror-selected", ("position: absolute; left: " + left + "px;\n                             top: " + top + "px; width: " + (width == null ? rightSide - left : width) + "px;\n                             height: " + (bottom - top) + "px")));
    }

    function drawForLine(line, fromArg, toArg) {
        var lineObj = getLine(doc, line);
        var lineLen = lineObj.text.length;
        var start, end;

        function coords(ch, bias) {
            return charCoords(cm, Pos(line, ch), "div", lineObj, bias)
        }

        function wrapX(pos, dir, side) {
            var extent = wrappedLineExtentChar(cm, lineObj, null, pos);
            var prop = (dir == "ltr") == (side == "after") ? "left" : "right";
            var ch = side == "after" ? extent.begin : extent.end - (/\s/.test(lineObj.text.charAt(extent.end - 1)) ? 2 : 1);
            return coords(ch, prop)[prop]
        }

        var order = getOrder(lineObj, doc.direction);
        iterateBidiSections(order, fromArg || 0, toArg == null ? lineLen : toArg, function (from, to, dir, i) {
            var ltr = dir == "ltr";
            var fromPos = coords(from, ltr ? "left" : "right");
            var toPos = coords(to - 1, ltr ? "right" : "left");

            var openStart = fromArg == null && from == 0, openEnd = toArg == null && to == lineLen;
            var first = i == 0, last = !order || i == order.length - 1;
            if (toPos.top - fromPos.top <= 3) { // Single line
                var openLeft = (docLTR ? openStart : openEnd) && first;
                var openRight = (docLTR ? openEnd : openStart) && last;
                var left = openLeft ? leftSide : (ltr ? fromPos : toPos).left;
                var right = openRight ? rightSide : (ltr ? toPos : fromPos).right;
                add(left, fromPos.top, right - left, fromPos.bottom);
            } else { // Multiple lines
                var topLeft, topRight, botLeft, botRight;
                if (ltr) {
                    topLeft = docLTR && openStart && first ? leftSide : fromPos.left;
                    topRight = docLTR ? rightSide : wrapX(from, dir, "before");
                    botLeft = docLTR ? leftSide : wrapX(to, dir, "after");
                    botRight = docLTR && openEnd && last ? rightSide : toPos.right;
                } else {
                    topLeft = !docLTR ? leftSide : wrapX(from, dir, "before");
                    topRight = !docLTR && openStart && first ? rightSide : fromPos.right;
                    botLeft = !docLTR && openEnd && last ? leftSide : toPos.left;
                    botRight = !docLTR ? rightSide : wrapX(to, dir, "after");
                }
                add(topLeft, fromPos.top, topRight - topLeft, fromPos.bottom);
                if (fromPos.bottom < toPos.top) {
                    add(leftSide, fromPos.bottom, null, toPos.top);
                }
                add(botLeft, toPos.top, botRight - botLeft, toPos.bottom);
            }

            if (!start || cmpCoords(fromPos, start) < 0) {
                start = fromPos;
            }
            if (cmpCoords(toPos, start) < 0) {
                start = toPos;
            }
            if (!end || cmpCoords(fromPos, end) < 0) {
                end = fromPos;
            }
            if (cmpCoords(toPos, end) < 0) {
                end = toPos;
            }
        });
        return {start: start, end: end}
    }

    var sFrom = range$$1.from(), sTo = range$$1.to();
    if (sFrom.line == sTo.line) {
        drawForLine(sFrom.line, sFrom.ch, sTo.ch);
    } else {
        var fromLine = getLine(doc, sFrom.line), toLine = getLine(doc, sTo.line);
        var singleVLine = visualLine(fromLine) == visualLine(toLine);
        var leftEnd = drawForLine(sFrom.line, sFrom.ch, singleVLine ? fromLine.text.length + 1 : null).end;
        var rightStart = drawForLine(sTo.line, singleVLine ? 0 : null, sTo.ch).start;
        if (singleVLine) {
            if (leftEnd.top < rightStart.top - 2) {
                add(leftEnd.right, leftEnd.top, null, leftEnd.bottom);
                add(leftSide, rightStart.top, rightStart.left, rightStart.bottom);
            } else {
                add(leftEnd.right, leftEnd.top, rightStart.left - leftEnd.right, leftEnd.bottom);
            }
        }
        if (leftEnd.bottom < rightStart.top) {
            add(leftSide, leftEnd.bottom, null, rightStart.top);
        }
    }

    output.appendChild(fragment);
}

// Cursor-blinking
function restartBlink(cm) {
    if (!cm.state.focused) {
        return
    }
    var display = cm.display;
    clearInterval(display.blinker);
    var on = true;
    display.cursorDiv.style.visibility = "";
    if (cm.options.cursorBlinkRate > 0) {
        display.blinker = setInterval(function () {
                return display.cursorDiv.style.visibility = (on = !on) ? "" : "hidden";
            },
            cm.options.cursorBlinkRate);
    } else if (cm.options.cursorBlinkRate < 0) {
        display.cursorDiv.style.visibility = "hidden";
    }
}

function ensureFocus(cm) {
    if (!cm.state.focused) {
        cm.display.input.focus();
        onFocus(cm);
    }
}

function delayBlurEvent(cm) {
    cm.state.delayingBlurEvent = true;
    setTimeout(function () {
        if (cm.state.delayingBlurEvent) {
            cm.state.delayingBlurEvent = false;
            onBlur(cm);
        }
    }, 100);
}

function onFocus(cm, e) {
    if (cm.state.delayingBlurEvent) {
        cm.state.delayingBlurEvent = false;
    }

    if (cm.options.readOnly == "nocursor") {
        return
    }
    if (!cm.state.focused) {
        signal(cm, "focus", cm, e);
        cm.state.focused = true;
        addClass(cm.display.wrapper, "CodeMirror-focused");
        // This test prevents this from firing when a context
        // menu is closed (since the input reset would kill the
        // select-all detection hack)
        if (!cm.curOp && cm.display.selForContextMenu != cm.doc.sel) {
            cm.display.input.reset();
            if (webkit) {
                setTimeout(function () {
                    return cm.display.input.reset(true);
                }, 20);
            } // Issue #1730
        }
        cm.display.input.receivedFocus();
    }
    restartBlink(cm);
}

function onBlur(cm, e) {
    if (cm.state.delayingBlurEvent) {
        return
    }

    if (cm.state.focused) {
        signal(cm, "blur", cm, e);
        cm.state.focused = false;
        rmClass(cm.display.wrapper, "CodeMirror-focused");
    }
    clearInterval(cm.display.blinker);
    setTimeout(function () {
        if (!cm.state.focused) {
            cm.display.shift = false;
        }
    }, 150);
}

// Read the actual heights of the rendered lines, and update their
// stored heights to match.
function updateHeightsInViewport(cm) {
    var display = cm.display;
    var prevBottom = display.lineDiv.offsetTop;
    for (var i = 0; i < display.view.length; i++) {
        var cur = display.view[i], wrapping = cm.options.lineWrapping;
        var height = (void 0), width = 0;
        if (cur.hidden) {
            continue
        }
        if (ie && ie_version < 8) {
            var bot = cur.node.offsetTop + cur.node.offsetHeight;
            height = bot - prevBottom;
            prevBottom = bot;
        } else {
            var box = cur.node.getBoundingClientRect();
            height = box.bottom - box.top;
            // Check that lines don't extend past the right of the current
            // src width
            if (!wrapping && cur.text.firstChild) {
                width = cur.text.firstChild.getBoundingClientRect().right - box.left - 1;
            }
        }
        var diff = cur.line.height - height;
        if (diff > .005 || diff < -.005) {
            updateLineHeight(cur.line, height);
            updateWidgetHeight(cur.line);
            if (cur.rest) {
                for (var j = 0; j < cur.rest.length; j++) {
                    updateWidgetHeight(cur.rest[j]);
                }
            }
        }
        if (width > cm.display.sizerWidth) {
            var chWidth = Math.ceil(width / charWidth(cm.display));
            if (chWidth > cm.display.maxLineLength) {
                cm.display.maxLineLength = chWidth;
                cm.display.maxLine = cur.line;
                cm.display.maxLineChanged = true;
            }
        }
    }
}

// Read and store the height of line widgets associated with the
// given line.
function updateWidgetHeight(line) {
    if (line.widgets) {
        for (var i = 0; i < line.widgets.length; ++i) {
            var w = line.widgets[i], parent = w.node.parentNode;
            if (parent) {
                w.height = parent.offsetHeight;
            }
        }
    }
}

// Compute the lines that are visible in a given viewport (defaults
// the the current scroll position). viewport may contain top,
// height, and ensure (see op.scrollToPos) properties.
function visibleLines(display, doc, viewport) {
    var top = viewport && viewport.top != null ? Math.max(0, viewport.top) : display.scroller.scrollTop;
    top = Math.floor(top - paddingTop(display));
    var bottom = viewport && viewport.bottom != null ? viewport.bottom : top + display.wrapper.clientHeight;

    var from = lineAtHeight(doc, top), to = lineAtHeight(doc, bottom);
    // Ensure is a {from: {line, ch}, to: {line, ch}} object, and
    // forces those lines into the viewport (if possible).
    if (viewport && viewport.ensure) {
        var ensureFrom = viewport.ensure.from.line, ensureTo = viewport.ensure.to.line;
        if (ensureFrom < from) {
            from = ensureFrom;
            to = lineAtHeight(doc, heightAtLine(getLine(doc, ensureFrom)) + display.wrapper.clientHeight);
        } else if (Math.min(ensureTo, doc.lastLine()) >= to) {
            from = lineAtHeight(doc, heightAtLine(getLine(doc, ensureTo)) - display.wrapper.clientHeight);
            to = ensureTo;
        }
    }
    return {from: from, to: Math.max(to, from + 1)}
}

// SCROLLING THINGS INTO VIEW

// If an src sits on the top or bottom of the window, partially
// scrolled out of view, this ensures that the cursor is visible.
function maybeScrollWindow(cm, rect) {
    if (signalDOMEvent(cm, "scrollCursorIntoView")) {
        return
    }

    var display = cm.display, box = display.sizer.getBoundingClientRect(), doScroll = null;
    if (rect.top + box.top < 0) {
        doScroll = true;
    } else if (rect.bottom + box.top > (window.innerHeight || document.documentElement.clientHeight)) {
        doScroll = false;
    }
    if (doScroll != null && !phantom) {
        var scrollNode = elt("div", "\u200b", null, ("position: absolute;\n                         top: " + (rect.top - display.viewOffset - paddingTop(cm.display)) + "px;\n                         height: " + (rect.bottom - rect.top + scrollGap(cm) + display.barHeight) + "px;\n                         left: " + (rect.left) + "px; width: " + (Math.max(2, rect.right - rect.left)) + "px;"));
        cm.display.lineSpace.appendChild(scrollNode);
        scrollNode.scrollIntoView(doScroll);
        cm.display.lineSpace.removeChild(scrollNode);
    }
}

// Scroll a given position into view (immediately), verifying that
// it actually became visible (as line heights are accurately
// measured, the position of something may 'drift' during drawing).
function scrollPosIntoView(cm, pos, end, margin) {
    if (margin == null) {
        margin = 0;
    }
    var rect;
    if (!cm.options.lineWrapping && pos == end) {
        // Set pos and end to the cursor positions around the character pos sticks to
        // If pos.sticky == "before", that is around pos.ch - 1, otherwise around pos.ch
        // If pos == Pos(_, 0, "before"), pos and end are unchanged
        pos = pos.ch ? Pos(pos.line, pos.sticky == "before" ? pos.ch - 1 : pos.ch, "after") : pos;
        end = pos.sticky == "before" ? Pos(pos.line, pos.ch + 1, "before") : pos;
    }
    for (var limit = 0; limit < 5; limit++) {
        var changed = false;
        var coords = cursorCoords(cm, pos);
        var endCoords = !end || end == pos ? coords : cursorCoords(cm, end);
        rect = {
            left: Math.min(coords.left, endCoords.left),
            top: Math.min(coords.top, endCoords.top) - margin,
            right: Math.max(coords.left, endCoords.left),
            bottom: Math.max(coords.bottom, endCoords.bottom) + margin
        };
        var scrollPos = calculateScrollPos(cm, rect);
        var startTop = cm.doc.scrollTop, startLeft = cm.doc.scrollLeft;
        if (scrollPos.scrollTop != null) {
            updateScrollTop(cm, scrollPos.scrollTop);
            if (Math.abs(cm.doc.scrollTop - startTop) > 1) {
                changed = true;
            }
        }
        if (scrollPos.scrollLeft != null) {
            setScrollLeft(cm, scrollPos.scrollLeft);
            if (Math.abs(cm.doc.scrollLeft - startLeft) > 1) {
                changed = true;
            }
        }
        if (!changed) {
            break
        }
    }
    return rect
}

// Scroll a given set of coordinates into view (immediately).
function scrollIntoView(cm, rect) {
    var scrollPos = calculateScrollPos(cm, rect);
    if (scrollPos.scrollTop != null) {
        updateScrollTop(cm, scrollPos.scrollTop);
    }
    if (scrollPos.scrollLeft != null) {
        setScrollLeft(cm, scrollPos.scrollLeft);
    }
}

// Calculate a new scroll position needed to scroll the given
// rectangle into view. Returns an object with scrollTop and
// scrollLeft properties. When these are undefined, the
// vertical/horizontal position does not need to be adjusted.
function calculateScrollPos(cm, rect) {
    var display = cm.display, snapMargin = textHeight(cm.display);
    if (rect.top < 0) {
        rect.top = 0;
    }
    var screentop = cm.curOp && cm.curOp.scrollTop != null ? cm.curOp.scrollTop : display.scroller.scrollTop;
    var screen = displayHeight(cm), result = {};
    if (rect.bottom - rect.top > screen) {
        rect.bottom = rect.top + screen;
    }
    var docBottom = cm.doc.height + paddingVert(display);
    var atTop = rect.top < snapMargin, atBottom = rect.bottom > docBottom - snapMargin;
    if (rect.top < screentop) {
        result.scrollTop = atTop ? 0 : rect.top;
    } else if (rect.bottom > screentop + screen) {
        var newTop = Math.min(rect.top, (atBottom ? docBottom : rect.bottom) - screen);
        if (newTop != screentop) {
            result.scrollTop = newTop;
        }
    }

    var screenleft = cm.curOp && cm.curOp.scrollLeft != null ? cm.curOp.scrollLeft : display.scroller.scrollLeft;
    var screenw = displayWidth(cm) - (cm.options.fixedGutter ? display.gutters.offsetWidth : 0);
    var tooWide = rect.right - rect.left > screenw;
    if (tooWide) {
        rect.right = rect.left + screenw;
    }
    if (rect.left < 10) {
        result.scrollLeft = 0;
    } else if (rect.left < screenleft) {
        result.scrollLeft = Math.max(0, rect.left - (tooWide ? 0 : 10));
    } else if (rect.right > screenw + screenleft - 3) {
        result.scrollLeft = rect.right + (tooWide ? 0 : 10) - screenw;
    }
    return result
}

// Store a relative adjustment to the scroll position in the current
// operation (to be applied when the operation finishes).
function addToScrollTop(cm, top) {
    if (top == null) {
        return
    }
    resolveScrollToPos(cm);
    cm.curOp.scrollTop = (cm.curOp.scrollTop == null ? cm.doc.scrollTop : cm.curOp.scrollTop) + top;
}

// Make sure that at the end of the operation the current cursor is
// shown.
function ensureCursorVisible(cm) {
    resolveScrollToPos(cm);
    var cur = cm.getCursor();
    cm.curOp.scrollToPos = {from: cur, to: cur, margin: cm.options.cursorScrollMargin};
}

function scrollToCoords(cm, x, y) {
    if (x != null || y != null) {
        resolveScrollToPos(cm);
    }
    if (x != null) {
        cm.curOp.scrollLeft = x;
    }
    if (y != null) {
        cm.curOp.scrollTop = y;
    }
}

function scrollToRange(cm, range$$1) {
    resolveScrollToPos(cm);
    cm.curOp.scrollToPos = range$$1;
}

// When an operation has its scrollToPos property set, and another
// scroll action is applied before the end of the operation, this
// 'simulates' scrolling that position into view in a cheap way, so
// that the effect of intermediate scroll commands is not ignored.
function resolveScrollToPos(cm) {
    var range$$1 = cm.curOp.scrollToPos;
    if (range$$1) {
        cm.curOp.scrollToPos = null;
        var from = estimateCoords(cm, range$$1.from), to = estimateCoords(cm, range$$1.to);
        scrollToCoordsRange(cm, from, to, range$$1.margin);
    }
}

function scrollToCoordsRange(cm, from, to, margin) {
    var sPos = calculateScrollPos(cm, {
        left: Math.min(from.left, to.left),
        top: Math.min(from.top, to.top) - margin,
        right: Math.max(from.right, to.right),
        bottom: Math.max(from.bottom, to.bottom) + margin
    });
    scrollToCoords(cm, sPos.scrollLeft, sPos.scrollTop);
}

// Sync the scrollable area and scrollbars, ensure the viewport
// covers the visible area.
function updateScrollTop(cm, val) {
    if (Math.abs(cm.doc.scrollTop - val) < 2) {
        return
    }
    if (!gecko) {
        updateDisplaySimple(cm, {top: val});
    }
    setScrollTop(cm, val, true);
    if (gecko) {
        updateDisplaySimple(cm);
    }
    startWorker(cm, 100);
}

function setScrollTop(cm, val, forceScroll) {
    val = Math.min(cm.display.scroller.scrollHeight - cm.display.scroller.clientHeight, val);
    if (cm.display.scroller.scrollTop == val && !forceScroll) {
        return
    }
    cm.doc.scrollTop = val;
    cm.display.scrollbars.setScrollTop(val);
    if (cm.display.scroller.scrollTop != val) {
        cm.display.scroller.scrollTop = val;
    }
}

// Sync scroller and scrollbar, ensure the gutter elements are
// aligned.
function setScrollLeft(cm, val, isScroller, forceScroll) {
    val = Math.min(val, cm.display.scroller.scrollWidth - cm.display.scroller.clientWidth);
    if ((isScroller ? val == cm.doc.scrollLeft : Math.abs(cm.doc.scrollLeft - val) < 2) && !forceScroll) {
        return
    }
    cm.doc.scrollLeft = val;
    alignHorizontally(cm);
    if (cm.display.scroller.scrollLeft != val) {
        cm.display.scroller.scrollLeft = val;
    }
    cm.display.scrollbars.setScrollLeft(val);
}

// SCROLLBARS

// Prepare DOM reads needed to update the scrollbars. Done in one
// shot to minimize update/measure roundtrips.
function measureForScrollbars(cm) {
    var d = cm.display, gutterW = d.gutters.offsetWidth;
    var docH = Math.round(cm.doc.height + paddingVert(cm.display));
    return {
        clientHeight: d.scroller.clientHeight,
        viewHeight: d.wrapper.clientHeight,
        scrollWidth: d.scroller.scrollWidth, clientWidth: d.scroller.clientWidth,
        viewWidth: d.wrapper.clientWidth,
        barLeft: cm.options.fixedGutter ? gutterW : 0,
        docHeight: docH,
        scrollHeight: docH + scrollGap(cm) + d.barHeight,
        nativeBarWidth: d.nativeBarWidth,
        gutterWidth: gutterW
    }
}

var NativeScrollbars = function (place, scroll, cm) {
    this.cm = cm;
    var vert = this.vert = elt("div", [elt("div", null, null, "min-width: 1px")], "CodeMirror-vscrollbar");
    var horiz = this.horiz = elt("div", [elt("div", null, null, "height: 100%; min-height: 1px")], "CodeMirror-hscrollbar");
    vert.tabIndex = horiz.tabIndex = -1;
    place(vert);
    place(horiz);

    on(vert, "scroll", function () {
        if (vert.clientHeight) {
            scroll(vert.scrollTop, "vertical");
        }
    });
    on(horiz, "scroll", function () {
        if (horiz.clientWidth) {
            scroll(horiz.scrollLeft, "horizontal");
        }
    });

    this.checkedZeroWidth = false;
    // Need to set a minimum width to see the scrollbar on IE7 (but must not set it on IE8).
    if (ie && ie_version < 8) {
        this.horiz.style.minHeight = this.vert.style.minWidth = "18px";
    }
};

NativeScrollbars.prototype.update = function (measure) {
    var needsH = measure.scrollWidth > measure.clientWidth + 1;
    var needsV = measure.scrollHeight > measure.clientHeight + 1;
    var sWidth = measure.nativeBarWidth;

    if (needsV) {
        this.vert.style.display = "block";
        this.vert.style.bottom = needsH ? sWidth + "px" : "0";
        var totalHeight = measure.viewHeight - (needsH ? sWidth : 0);
        // A bug in IE8 can cause this value to be negative, so guard it.
        this.vert.firstChild.style.height =
            Math.max(0, measure.scrollHeight - measure.clientHeight + totalHeight) + "px";
    } else {
        this.vert.style.display = "";
        this.vert.firstChild.style.height = "0";
    }

    if (needsH) {
        this.horiz.style.display = "block";
        this.horiz.style.right = needsV ? sWidth + "px" : "0";
        this.horiz.style.left = measure.barLeft + "px";
        var totalWidth = measure.viewWidth - measure.barLeft - (needsV ? sWidth : 0);
        this.horiz.firstChild.style.width =
            Math.max(0, measure.scrollWidth - measure.clientWidth + totalWidth) + "px";
    } else {
        this.horiz.style.display = "";
        this.horiz.firstChild.style.width = "0";
    }

    if (!this.checkedZeroWidth && measure.clientHeight > 0) {
        if (sWidth == 0) {
            this.zeroWidthHack();
        }
        this.checkedZeroWidth = true;
    }

    return {right: needsV ? sWidth : 0, bottom: needsH ? sWidth : 0}
};

NativeScrollbars.prototype.setScrollLeft = function (pos) {
    if (this.horiz.scrollLeft != pos) {
        this.horiz.scrollLeft = pos;
    }
    if (this.disableHoriz) {
        this.enableZeroWidthBar(this.horiz, this.disableHoriz, "horiz");
    }
};

NativeScrollbars.prototype.setScrollTop = function (pos) {
    if (this.vert.scrollTop != pos) {
        this.vert.scrollTop = pos;
    }
    if (this.disableVert) {
        this.enableZeroWidthBar(this.vert, this.disableVert, "vert");
    }
};

NativeScrollbars.prototype.zeroWidthHack = function () {
    var w = mac && !mac_geMountainLion ? "12px" : "18px";
    this.horiz.style.height = this.vert.style.width = w;
    this.horiz.style.pointerEvents = this.vert.style.pointerEvents = "none";
    this.disableHoriz = new Delayed;
    this.disableVert = new Delayed;
};

NativeScrollbars.prototype.enableZeroWidthBar = function (bar, delay, type) {
    bar.style.pointerEvents = "auto";

    function maybeDisable() {
        // To find out whether the scrollbar is still visible, we
        // check whether the element under the pixel in the bottom
        // right corner of the scrollbar box is the scrollbar box
        // itself (when the bar is still visible) or its filler child
        // (when the bar is hidden). If it is still visible, we keep
        // it enabled, if it's hidden, we disable pointer events.
        var box = bar.getBoundingClientRect();
        var elt$$1 = type == "vert" ? document.elementFromPoint(box.right - 1, (box.top + box.bottom) / 2)
            : document.elementFromPoint((box.right + box.left) / 2, box.bottom - 1);
        if (elt$$1 != bar) {
            bar.style.pointerEvents = "none";
        } else {
            delay.set(1000, maybeDisable);
        }
    }

    delay.set(1000, maybeDisable);
};

NativeScrollbars.prototype.clear = function () {
    var parent = this.horiz.parentNode;
    parent.removeChild(this.horiz);
    parent.removeChild(this.vert);
};

var NullScrollbars = function () {
};

NullScrollbars.prototype.update = function () {
    return {bottom: 0, right: 0}
};
NullScrollbars.prototype.setScrollLeft = function () {
};
NullScrollbars.prototype.setScrollTop = function () {
};
NullScrollbars.prototype.clear = function () {
};

function updateScrollbars(cm, measure) {
    if (!measure) {
        measure = measureForScrollbars(cm);
    }
    var startWidth = cm.display.barWidth, startHeight = cm.display.barHeight;
    updateScrollbarsInner(cm, measure);
    for (var i = 0; i < 4 && startWidth != cm.display.barWidth || startHeight != cm.display.barHeight; i++) {
        if (startWidth != cm.display.barWidth && cm.options.lineWrapping) {
            updateHeightsInViewport(cm);
        }
        updateScrollbarsInner(cm, measureForScrollbars(cm));
        startWidth = cm.display.barWidth;
        startHeight = cm.display.barHeight;
    }
}

// Re-synchronize the fake scrollbars with the actual size of the
// content.
function updateScrollbarsInner(cm, measure) {
    var d = cm.display;
    var sizes = d.scrollbars.update(measure);

    d.sizer.style.paddingRight = (d.barWidth = sizes.right) + "px";
    d.sizer.style.paddingBottom = (d.barHeight = sizes.bottom) + "px";
    d.heightForcer.style.borderBottom = sizes.bottom + "px solid transparent";

    if (sizes.right && sizes.bottom) {
        d.scrollbarFiller.style.display = "block";
        d.scrollbarFiller.style.height = sizes.bottom + "px";
        d.scrollbarFiller.style.width = sizes.right + "px";
    } else {
        d.scrollbarFiller.style.display = "";
    }
    if (sizes.bottom && cm.options.coverGutterNextToScrollbar && cm.options.fixedGutter) {
        d.gutterFiller.style.display = "block";
        d.gutterFiller.style.height = sizes.bottom + "px";
        d.gutterFiller.style.width = measure.gutterWidth + "px";
    } else {
        d.gutterFiller.style.display = "";
    }
}

var scrollbarModel = {"native": NativeScrollbars, "null": NullScrollbars};

function initScrollbars(cm) {
    if (cm.display.scrollbars) {
        cm.display.scrollbars.clear();
        if (cm.display.scrollbars.addClass) {
            rmClass(cm.display.wrapper, cm.display.scrollbars.addClass);
        }
    }

    cm.display.scrollbars = new scrollbarModel[cm.options.scrollbarStyle](function (node) {
        cm.display.wrapper.insertBefore(node, cm.display.scrollbarFiller);
        // Prevent clicks in the scrollbars from killing focus
        on(node, "mousedown", function () {
            if (cm.state.focused) {
                setTimeout(function () {
                    return cm.display.input.focus();
                }, 0);
            }
        });
        node.setAttribute("cm-not-content", "true");
    }, function (pos, axis) {
        if (axis == "horizontal") {
            setScrollLeft(cm, pos);
        } else {
            updateScrollTop(cm, pos);
        }
    }, cm);
    if (cm.display.scrollbars.addClass) {
        addClass(cm.display.wrapper, cm.display.scrollbars.addClass);
    }
}

// Operations are used to wrap a series of changes to the src
// state in such a way that each change won't have to update the
// cursor and display (which would be awkward, slow, and
// error-prone). Instead, display updates are batched and then all
// combined and executed at once.

var nextOpId = 0;

// Start a new operation.
function startOperation(cm) {
    cm.curOp = {
        cm: cm,
        viewChanged: false,      // Flag that indicates that lines might need to be redrawn
        startHeight: cm.doc.height, // Used to detect need to update scrollbar
        forceUpdate: false,      // Used to force a redraw
        updateInput: 0,       // Whether to reset the input textarea
        typing: false,           // Whether this reset should be careful to leave existing text (for compositing)
        changeObjs: null,        // Accumulated changes, for firing change events
        cursorActivityHandlers: null, // Set of handlers to fire cursorActivity on
        cursorActivityCalled: 0, // Tracks which cursorActivity handlers have been called already
        selectionChanged: false, // Whether the selection needs to be redrawn
        updateMaxLine: false,    // Set when the widest line needs to be determined anew
        scrollLeft: null, scrollTop: null, // Intermediate scroll position, not pushed to DOM yet
        scrollToPos: null,       // Used to scroll to a specific position
        focus: false,
        id: ++nextOpId           // Unique ID
    };
    pushOperation(cm.curOp);
}

// Finish an operation, updating the display and signalling delayed events
function endOperation(cm) {
    var op = cm.curOp;
    if (op) {
        finishOperation(op, function (group) {
            for (var i = 0; i < group.ops.length; i++) {
                group.ops[i].cm.curOp = null;
            }
            endOperations(group);
        });
    }
}

// The DOM updates done when an operation finishes are batched so
// that the minimum number of relayouts are required.
function endOperations(group) {
    var ops = group.ops;
    for (var i = 0; i < ops.length; i++) // Read DOM
    {
        endOperation_R1(ops[i]);
    }
    for (var i$1 = 0; i$1 < ops.length; i$1++) // Write DOM (maybe)
    {
        endOperation_W1(ops[i$1]);
    }
    for (var i$2 = 0; i$2 < ops.length; i$2++) // Read DOM
    {
        endOperation_R2(ops[i$2]);
    }
    for (var i$3 = 0; i$3 < ops.length; i$3++) // Write DOM (maybe)
    {
        endOperation_W2(ops[i$3]);
    }
    for (var i$4 = 0; i$4 < ops.length; i$4++) // Read DOM
    {
        endOperation_finish(ops[i$4]);
    }
}

function endOperation_R1(op) {
    var cm = op.cm, display = cm.display;
    maybeClipScrollbars(cm);
    if (op.updateMaxLine) {
        findMaxLine(cm);
    }

    op.mustUpdate = op.viewChanged || op.forceUpdate || op.scrollTop != null ||
        op.scrollToPos && (op.scrollToPos.from.line < display.viewFrom ||
            op.scrollToPos.to.line >= display.viewTo) ||
        display.maxLineChanged && cm.options.lineWrapping;
    op.update = op.mustUpdate &&
        new DisplayUpdate(cm, op.mustUpdate && {top: op.scrollTop, ensure: op.scrollToPos}, op.forceUpdate);
}

function endOperation_W1(op) {
    op.updatedDisplay = op.mustUpdate && updateDisplayIfNeeded(op.cm, op.update);
}

function endOperation_R2(op) {
    var cm = op.cm, display = cm.display;
    if (op.updatedDisplay) {
        updateHeightsInViewport(cm);
    }

    op.barMeasure = measureForScrollbars(cm);

    // If the max line changed since it was last measured, measure it,
    // and ensure the document's width matches it.
    // updateDisplay_W2 will use these properties to do the actual resizing
    if (display.maxLineChanged && !cm.options.lineWrapping) {
        op.adjustWidthTo = measureChar(cm, display.maxLine, display.maxLine.text.length).left + 3;
        cm.display.sizerWidth = op.adjustWidthTo;
        op.barMeasure.scrollWidth =
            Math.max(display.scroller.clientWidth, display.sizer.offsetLeft + op.adjustWidthTo + scrollGap(cm) + cm.display.barWidth);
        op.maxScrollLeft = Math.max(0, display.sizer.offsetLeft + op.adjustWidthTo - displayWidth(cm));
    }

    if (op.updatedDisplay || op.selectionChanged) {
        op.preparedSelection = display.input.prepareSelection();
    }
}

function endOperation_W2(op) {
    var cm = op.cm;

    if (op.adjustWidthTo != null) {
        cm.display.sizer.style.minWidth = op.adjustWidthTo + "px";
        if (op.maxScrollLeft < cm.doc.scrollLeft) {
            setScrollLeft(cm, Math.min(cm.display.scroller.scrollLeft, op.maxScrollLeft), true);
        }
        cm.display.maxLineChanged = false;
    }

    var takeFocus = op.focus && op.focus == activeElt();
    if (op.preparedSelection) {
        cm.display.input.showSelection(op.preparedSelection, takeFocus);
    }
    if (op.updatedDisplay || op.startHeight != cm.doc.height) {
        updateScrollbars(cm, op.barMeasure);
    }
    if (op.updatedDisplay) {
        setDocumentHeight(cm, op.barMeasure);
    }

    if (op.selectionChanged) {
        restartBlink(cm);
    }

    if (cm.state.focused && op.updateInput) {
        cm.display.input.reset(op.typing);
    }
    if (takeFocus) {
        ensureFocus(op.cm);
    }
}

function endOperation_finish(op) {
    var cm = op.cm, display = cm.display, doc = cm.doc;

    if (op.updatedDisplay) {
        postUpdateDisplay(cm, op.update);
    }

    // Abort mouse wheel delta measurement, when scrolling explicitly
    if (display.wheelStartX != null && (op.scrollTop != null || op.scrollLeft != null || op.scrollToPos)) {
        display.wheelStartX = display.wheelStartY = null;
    }

    // Propagate the scroll position to the actual DOM scroller
    if (op.scrollTop != null) {
        setScrollTop(cm, op.scrollTop, op.forceScroll);
    }

    if (op.scrollLeft != null) {
        setScrollLeft(cm, op.scrollLeft, true, true);
    }
    // If we need to scroll a specific position into view, do so.
    if (op.scrollToPos) {
        var rect = scrollPosIntoView(cm, clipPos(doc, op.scrollToPos.from),
            clipPos(doc, op.scrollToPos.to), op.scrollToPos.margin);
        maybeScrollWindow(cm, rect);
    }

    // Fire events for markers that are hidden/unidden by editing or
    // undoing
    var hidden = op.maybeHiddenMarkers, unhidden = op.maybeUnhiddenMarkers;
    if (hidden) {
        for (var i = 0; i < hidden.length; ++i) {
            if (!hidden[i].lines.length) {
                signal(hidden[i], "hide");
            }
        }
    }
    if (unhidden) {
        for (var i$1 = 0; i$1 < unhidden.length; ++i$1) {
            if (unhidden[i$1].lines.length) {
                signal(unhidden[i$1], "unhide");
            }
        }
    }

    if (display.wrapper.offsetHeight) {
        doc.scrollTop = cm.display.scroller.scrollTop;
    }

    // Fire change events, and delayed event handlers
    if (op.changeObjs) {
        signal(cm, "changes", cm, op.changeObjs);
    }
    if (op.update) {
        op.update.finish();
    }
}

// Run the given function in an operation
function runInOp(cm, f) {
    if (cm.curOp) {
        return f()
    }
    startOperation(cm);
    try {
        return f()
    } finally {
        endOperation(cm);
    }
}

// Wraps a function in an operation. Returns the wrapped function.
function operation(cm, f) {
    return function () {
        if (cm.curOp) {
            return f.apply(cm, arguments)
        }
        startOperation(cm);
        try {
            return f.apply(cm, arguments)
        } finally {
            endOperation(cm);
        }
    }
}

// Used to add methods to src and docs instances, wrapping them in
// operations.
function methodOp(f) {
    return function () {
        if (this.curOp) {
            return f.apply(this, arguments)
        }
        startOperation(this);
        try {
            return f.apply(this, arguments)
        } finally {
            endOperation(this);
        }
    }
}

function docMethodOp(f) {
    return function () {
        var cm = this.cm;
        if (!cm || cm.curOp) {
            return f.apply(this, arguments)
        }
        startOperation(cm);
        try {
            return f.apply(this, arguments)
        } finally {
            endOperation(cm);
        }
    }
}

// HIGHLIGHT WORKER

function startWorker(cm, time) {
    if (cm.doc.highlightFrontier < cm.display.viewTo) {
        cm.state.highlight.set(time, bind(highlightWorker, cm));
    }
}

function highlightWorker(cm) {
    var doc = cm.doc;
    if (doc.highlightFrontier >= cm.display.viewTo) {
        return
    }
    var end = +new Date + cm.options.workTime;
    var context = getContextBefore(cm, doc.highlightFrontier);
    var changedLines = [];

    doc.iter(context.line, Math.min(doc.first + doc.size, cm.display.viewTo + 500), function (line) {
        if (context.line >= cm.display.viewFrom) { // Visible
            var oldStyles = line.styles;
            var resetState = line.text.length > cm.options.maxHighlightLength ? copyState(doc.mode, context.state) : null;
            var highlighted = highlightLine(cm, line, context, true);
            if (resetState) {
                context.state = resetState;
            }
            line.styles = highlighted.styles;
            var oldCls = line.styleClasses, newCls = highlighted.classes;
            if (newCls) {
                line.styleClasses = newCls;
            } else if (oldCls) {
                line.styleClasses = null;
            }
            var ischange = !oldStyles || oldStyles.length != line.styles.length ||
                oldCls != newCls && (!oldCls || !newCls || oldCls.bgClass != newCls.bgClass || oldCls.textClass != newCls.textClass);
            for (var i = 0; !ischange && i < oldStyles.length; ++i) {
                ischange = oldStyles[i] != line.styles[i];
            }
            if (ischange) {
                changedLines.push(context.line);
            }
            line.stateAfter = context.save();
            context.nextLine();
        } else {
            if (line.text.length <= cm.options.maxHighlightLength) {
                processLine(cm, line.text, context);
            }
            line.stateAfter = context.line % 5 == 0 ? context.save() : null;
            context.nextLine();
        }
        if (+new Date > end) {
            startWorker(cm, cm.options.workDelay);
            return true
        }
    });
    doc.highlightFrontier = context.line;
    doc.modeFrontier = Math.max(doc.modeFrontier, context.line);
    if (changedLines.length) {
        runInOp(cm, function () {
            for (var i = 0; i < changedLines.length; i++) {
                regLineChange(cm, changedLines[i], "text");
            }
        });
    }
}

// DISPLAY DRAWING

var DisplayUpdate = function (cm, viewport, force) {
    var display = cm.display;

    this.viewport = viewport;
    // Store some values that we'll need later (but don't want to force a relayout for)
    this.visible = visibleLines(display, cm.doc, viewport);
    this.editorIsHidden = !display.wrapper.offsetWidth;
    this.wrapperHeight = display.wrapper.clientHeight;
    this.wrapperWidth = display.wrapper.clientWidth;
    this.oldDisplayWidth = displayWidth(cm);
    this.force = force;
    this.dims = getDimensions(cm);
    this.events = [];
};

DisplayUpdate.prototype.signal = function (emitter, type) {
    if (hasHandler(emitter, type)) {
        this.events.push(arguments);
    }
};
DisplayUpdate.prototype.finish = function () {
    var this$1 = this;

    for (var i = 0; i < this.events.length; i++) {
        signal.apply(null, this$1.events[i]);
    }
};

function maybeClipScrollbars(cm) {
    var display = cm.display;
    if (!display.scrollbarsClipped && display.scroller.offsetWidth) {
        display.nativeBarWidth = display.scroller.offsetWidth - display.scroller.clientWidth;
        display.heightForcer.style.height = scrollGap(cm) + "px";
        display.sizer.style.marginBottom = -display.nativeBarWidth + "px";
        display.sizer.style.borderRightWidth = scrollGap(cm) + "px";
        display.scrollbarsClipped = true;
    }
}

function selectionSnapshot(cm) {
    if (cm.hasFocus()) {
        return null
    }
    var active = activeElt();
    if (!active || !contains(cm.display.lineDiv, active)) {
        return null
    }
    var result = {activeElt: active};
    if (window.getSelection) {
        var sel = window.getSelection();
        if (sel.anchorNode && sel.extend && contains(cm.display.lineDiv, sel.anchorNode)) {
            result.anchorNode = sel.anchorNode;
            result.anchorOffset = sel.anchorOffset;
            result.focusNode = sel.focusNode;
            result.focusOffset = sel.focusOffset;
        }
    }
    return result
}

function restoreSelection(snapshot) {
    if (!snapshot || !snapshot.activeElt || snapshot.activeElt == activeElt()) {
        return
    }
    snapshot.activeElt.focus();
    if (snapshot.anchorNode && contains(document.body, snapshot.anchorNode) && contains(document.body, snapshot.focusNode)) {
        var sel = window.getSelection(), range$$1 = document.createRange();
        range$$1.setEnd(snapshot.anchorNode, snapshot.anchorOffset);
        range$$1.collapse(false);
        sel.removeAllRanges();
        sel.addRange(range$$1);
        sel.extend(snapshot.focusNode, snapshot.focusOffset);
    }
}

// Does the actual updating of the line display. Bails out
// (returning false) when there is nothing to be done and forced is
// false.
function updateDisplayIfNeeded(cm, update) {
    var display = cm.display, doc = cm.doc;

    if (update.editorIsHidden) {
        resetView(cm);
        return false
    }

    // Bail out if the visible area is already rendered and nothing changed.
    if (!update.force &&
        update.visible.from >= display.viewFrom && update.visible.to <= display.viewTo &&
        (display.updateLineNumbers == null || display.updateLineNumbers >= display.viewTo) &&
        display.renderedView == display.view && countDirtyView(cm) == 0) {
        return false
    }

    if (maybeUpdateLineNumberWidth(cm)) {
        resetView(cm);
        update.dims = getDimensions(cm);
    }

    // Compute a suitable new viewport (from & to)
    var end = doc.first + doc.size;
    var from = Math.max(update.visible.from - cm.options.viewportMargin, doc.first);
    var to = Math.min(end, update.visible.to + cm.options.viewportMargin);
    if (display.viewFrom < from && from - display.viewFrom < 20) {
        from = Math.max(doc.first, display.viewFrom);
    }
    if (display.viewTo > to && display.viewTo - to < 20) {
        to = Math.min(end, display.viewTo);
    }
    if (sawCollapsedSpans) {
        from = visualLineNo(cm.doc, from);
        to = visualLineEndNo(cm.doc, to);
    }

    var different = from != display.viewFrom || to != display.viewTo ||
        display.lastWrapHeight != update.wrapperHeight || display.lastWrapWidth != update.wrapperWidth;
    adjustView(cm, from, to);

    display.viewOffset = heightAtLine(getLine(cm.doc, display.viewFrom));
    // Position the mover div to align with the current scroll position
    cm.display.mover.style.top = display.viewOffset + "px";

    var toUpdate = countDirtyView(cm);
    if (!different && toUpdate == 0 && !update.force && display.renderedView == display.view &&
        (display.updateLineNumbers == null || display.updateLineNumbers >= display.viewTo)) {
        return false
    }

    // For big changes, we hide the enclosing element during the
    // update, since that speeds up the operations on most browsers.
    var selSnapshot = selectionSnapshot(cm);
    if (toUpdate > 4) {
        display.lineDiv.style.display = "none";
    }
    patchDisplay(cm, display.updateLineNumbers, update.dims);
    if (toUpdate > 4) {
        display.lineDiv.style.display = "";
    }
    display.renderedView = display.view;
    // There might have been a widget with a focused element that got
    // hidden or updated, if so re-focus it.
    restoreSelection(selSnapshot);

    // Prevent selection and cursors from interfering with the scroll
    // width and height.
    removeChildren(display.cursorDiv);
    removeChildren(display.selectionDiv);
    display.gutters.style.height = display.sizer.style.minHeight = 0;

    if (different) {
        display.lastWrapHeight = update.wrapperHeight;
        display.lastWrapWidth = update.wrapperWidth;
        startWorker(cm, 400);
    }

    display.updateLineNumbers = null;

    return true
}

function postUpdateDisplay(cm, update) {
    var viewport = update.viewport;

    for (var first = true; ; first = false) {
        if (!first || !cm.options.lineWrapping || update.oldDisplayWidth == displayWidth(cm)) {
            // Clip forced viewport to actual scrollable area.
            if (viewport && viewport.top != null) {
                viewport = {top: Math.min(cm.doc.height + paddingVert(cm.display) - displayHeight(cm), viewport.top)};
            }
            // Updated line heights might result in the drawn area not
            // actually covering the viewport. Keep looping until it does.
            update.visible = visibleLines(cm.display, cm.doc, viewport);
            if (update.visible.from >= cm.display.viewFrom && update.visible.to <= cm.display.viewTo) {
                break
            }
        }
        if (!updateDisplayIfNeeded(cm, update)) {
            break
        }
        updateHeightsInViewport(cm);
        var barMeasure = measureForScrollbars(cm);
        updateSelection(cm);
        updateScrollbars(cm, barMeasure);
        setDocumentHeight(cm, barMeasure);
        update.force = false;
    }

    update.signal(cm, "update", cm);
    if (cm.display.viewFrom != cm.display.reportedViewFrom || cm.display.viewTo != cm.display.reportedViewTo) {
        update.signal(cm, "viewportChange", cm, cm.display.viewFrom, cm.display.viewTo);
        cm.display.reportedViewFrom = cm.display.viewFrom;
        cm.display.reportedViewTo = cm.display.viewTo;
    }
}

function updateDisplaySimple(cm, viewport) {
    var update = new DisplayUpdate(cm, viewport);
    if (updateDisplayIfNeeded(cm, update)) {
        updateHeightsInViewport(cm);
        postUpdateDisplay(cm, update);
        var barMeasure = measureForScrollbars(cm);
        updateSelection(cm);
        updateScrollbars(cm, barMeasure);
        setDocumentHeight(cm, barMeasure);
        update.finish();
    }
}

// Sync the actual display DOM structure with display.view, removing
// nodes for lines that are no longer in view, and creating the ones
// that are not there yet, and updating the ones that are out of
// date.
function patchDisplay(cm, updateNumbersFrom, dims) {
    var display = cm.display, lineNumbers = cm.options.lineNumbers;
    var container = display.lineDiv, cur = container.firstChild;

    function rm(node) {
        var next = node.nextSibling;
        // Works around a throw-scroll bug in OS X Webkit
        if (webkit && mac && cm.display.currentWheelTarget == node) {
            node.style.display = "none";
        } else {
            node.parentNode.removeChild(node);
        }
        return next
    }

    var view = display.view, lineN = display.viewFrom;
    // Loop over the elements in the view, syncing cur (the DOM nodes
    // in display.lineDiv) with the view as we go.
    for (var i = 0; i < view.length; i++) {
        var lineView = view[i];
        if (lineView.hidden) ; else if (!lineView.node || lineView.node.parentNode != container) { // Not drawn yet
            var node = buildLineElement(cm, lineView, lineN, dims);
            container.insertBefore(node, cur);
        } else { // Already drawn
            while (cur != lineView.node) {
                cur = rm(cur);
            }
            var updateNumber = lineNumbers && updateNumbersFrom != null &&
                updateNumbersFrom <= lineN && lineView.lineNumber;
            if (lineView.changes) {
                if (indexOf(lineView.changes, "gutter") > -1) {
                    updateNumber = false;
                }
                updateLineForChanges(cm, lineView, lineN, dims);
            }
            if (updateNumber) {
                removeChildren(lineView.lineNumber);
                lineView.lineNumber.appendChild(document.createTextNode(lineNumberFor(cm.options, lineN)));
            }
            cur = lineView.node.nextSibling;
        }
        lineN += lineView.size;
    }
    while (cur) {
        cur = rm(cur);
    }
}

function updateGutterSpace(display) {
    var width = display.gutters.offsetWidth;
    display.sizer.style.marginLeft = width + "px";
}

function setDocumentHeight(cm, measure) {
    cm.display.sizer.style.minHeight = measure.docHeight + "px";
    cm.display.heightForcer.style.top = measure.docHeight + "px";
    cm.display.gutters.style.height = (measure.docHeight + cm.display.barHeight + scrollGap(cm)) + "px";
}

// Re-align line numbers and gutter marks to compensate for
// horizontal scrolling.
function alignHorizontally(cm) {
    var display = cm.display, view = display.view;
    if (!display.alignWidgets && (!display.gutters.firstChild || !cm.options.fixedGutter)) {
        return
    }
    var comp = compensateForHScroll(display) - display.scroller.scrollLeft + cm.doc.scrollLeft;
    var gutterW = display.gutters.offsetWidth, left = comp + "px";
    for (var i = 0; i < view.length; i++) {
        if (!view[i].hidden) {
            if (cm.options.fixedGutter) {
                if (view[i].gutter) {
                    view[i].gutter.style.left = left;
                }
                if (view[i].gutterBackground) {
                    view[i].gutterBackground.style.left = left;
                }
            }
            var align = view[i].alignable;
            if (align) {
                for (var j = 0; j < align.length; j++) {
                    align[j].style.left = left;
                }
            }
        }
    }
    if (cm.options.fixedGutter) {
        display.gutters.style.left = (comp + gutterW) + "px";
    }
}

// Used to ensure that the line number gutter is still the right
// size for the current document size. Returns true when an update
// is needed.
function maybeUpdateLineNumberWidth(cm) {
    if (!cm.options.lineNumbers) {
        return false
    }
    var doc = cm.doc, last = lineNumberFor(cm.options, doc.first + doc.size - 1), display = cm.display;
    if (last.length != display.lineNumChars) {
        var test = display.measure.appendChild(elt("div", [elt("div", last)],
            "CodeMirror-linenumber CodeMirror-gutter-elt"));
        var innerW = test.firstChild.offsetWidth, padding = test.offsetWidth - innerW;
        display.lineGutter.style.width = "";
        display.lineNumInnerWidth = Math.max(innerW, display.lineGutter.offsetWidth - padding) + 1;
        display.lineNumWidth = display.lineNumInnerWidth + padding;
        display.lineNumChars = display.lineNumInnerWidth ? last.length : -1;
        display.lineGutter.style.width = display.lineNumWidth + "px";
        updateGutterSpace(cm.display);
        return true
    }
    return false
}

function getGutters(gutters, lineNumbers) {
    var result = [], sawLineNumbers = false;
    for (var i = 0; i < gutters.length; i++) {
        var name = gutters[i], style = null;
        if (typeof name != "string") {
            style = name.style;
            name = name.className;
        }
        if (name == "CodeMirror-linenumbers") {
            if (!lineNumbers) {
                continue
            } else {
                sawLineNumbers = true;
            }
        }
        result.push({className: name, style: style});
    }
    if (lineNumbers && !sawLineNumbers) {
        result.push({className: "CodeMirror-linenumbers", style: null});
    }
    return result
}

// Rebuild the gutter elements, ensure the margin to the left of the
// code matches their width.
function renderGutters(display) {
    var gutters = display.gutters, specs = display.gutterSpecs;
    removeChildren(gutters);
    display.lineGutter = null;
    for (var i = 0; i < specs.length; ++i) {
        var ref = specs[i];
        var className = ref.className;
        var style = ref.style;
        var gElt = gutters.appendChild(elt("div", null, "CodeMirror-gutter " + className));
        if (style) {
            gElt.style.cssText = style;
        }
        if (className == "CodeMirror-linenumbers") {
            display.lineGutter = gElt;
            gElt.style.width = (display.lineNumWidth || 1) + "px";
        }
    }
    gutters.style.display = specs.length ? "" : "none";
    updateGutterSpace(display);
}

function updateGutters(cm) {
    renderGutters(cm.display);
    regChange(cm);
    alignHorizontally(cm);
}

// The display handles the DOM integration, both for input reading
// and content drawing. It holds references to DOM nodes and
// display-related state.

function Display(place, doc, input, options) {
    var d = this;
    this.input = input;

    // Covers bottom-right square when both scrollbars are present.
    d.scrollbarFiller = elt("div", null, "CodeMirror-scrollbar-filler");
    d.scrollbarFiller.setAttribute("cm-not-content", "true");
    // Covers bottom of gutter when coverGutterNextToScrollbar is on
    // and h scrollbar is present.
    d.gutterFiller = elt("div", null, "CodeMirror-gutter-filler");
    d.gutterFiller.setAttribute("cm-not-content", "true");
    // Will contain the actual code, positioned to cover the viewport.
    d.lineDiv = eltP("div", null, "CodeMirror-code");
    // Elements are added to these to represent selection and cursors.
    d.selectionDiv = elt("div", null, null, "position: relative; z-index: 1");
    d.cursorDiv = elt("div", null, "CodeMirror-cursors");
    // A visibility: hidden element used to find the size of things.
    d.measure = elt("div", null, "CodeMirror-measure");
    // When lines outside of the viewport are measured, they are drawn in this.
    d.lineMeasure = elt("div", null, "CodeMirror-measure");
    // Wraps everything that needs to exist inside the vertically-padded coordinate system
    d.lineSpace = eltP("div", [d.measure, d.lineMeasure, d.selectionDiv, d.cursorDiv, d.lineDiv],
        null, "position: relative; outline: none");
    var lines = eltP("div", [d.lineSpace], "CodeMirror-lines");
    // Moved around its parent to cover visible view.
    d.mover = elt("div", [lines], null, "position: relative");
    // Set to the height of the document, allowing scrolling.
    d.sizer = elt("div", [d.mover], "CodeMirror-sizer");
    d.sizerWidth = null;
    // Behavior of elts with overflow: auto and padding is
    // inconsistent across browsers. This is used to ensure the
    // scrollable area is big enough.
    d.heightForcer = elt("div", null, null, "position: absolute; height: " + scrollerGap + "px; width: 1px;");
    // Will contain the gutters, if any.
    d.gutters = elt("div", null, "CodeMirror-gutters");
    d.lineGutter = null;
    // Actual scrollable element.
    d.scroller = elt("div", [d.sizer, d.heightForcer, d.gutters], "CodeMirror-scroll");
    d.scroller.setAttribute("tabIndex", "-1");
    // The element in which the src lives.
    d.wrapper = elt("div", [d.scrollbarFiller, d.gutterFiller, d.scroller], "CodeMirror");

    // Work around IE7 z-index bug (not perfect, hence IE7 not really being supported)
    if (ie && ie_version < 8) {
        d.gutters.style.zIndex = -1;
        d.scroller.style.paddingRight = 0;
    }
    if (!webkit && !(gecko && mobile)) {
        d.scroller.draggable = true;
    }

    if (place) {
        if (place.appendChild) {
            place.appendChild(d.wrapper);
        } else {
            place(d.wrapper);
        }
    }

    // Current rendered range (may be bigger than the view window).
    d.viewFrom = d.viewTo = doc.first;
    d.reportedViewFrom = d.reportedViewTo = doc.first;
    // Information about the rendered lines.
    d.view = [];
    d.renderedView = null;
    // Holds info about a single rendered line when it was rendered
    // for measurement, while not in view.
    d.externalMeasured = null;
    // Empty space (in pixels) above the view
    d.viewOffset = 0;
    d.lastWrapHeight = d.lastWrapWidth = 0;
    d.updateLineNumbers = null;

    d.nativeBarWidth = d.barHeight = d.barWidth = 0;
    d.scrollbarsClipped = false;

    // Used to only resize the line number gutter when necessary (when
    // the amount of lines crosses a boundary that makes its width change)
    d.lineNumWidth = d.lineNumInnerWidth = d.lineNumChars = null;
    // Set to true when a non-horizontal-scrolling line widget is
    // added. As an optimization, line widget aligning is skipped when
    // this is false.
    d.alignWidgets = false;

    d.cachedCharWidth = d.cachedTextHeight = d.cachedPaddingH = null;

    // Tracks the maximum line length so that the horizontal scrollbar
    // can be kept static when scrolling.
    d.maxLine = null;
    d.maxLineLength = 0;
    d.maxLineChanged = false;

    // Used for measuring wheel scrolling granularity
    d.wheelDX = d.wheelDY = d.wheelStartX = d.wheelStartY = null;

    // True when shift is held down.
    d.shift = false;

    // Used to track whether anything happened since the context menu
    // was opened.
    d.selForContextMenu = null;

    d.activeTouch = null;

    d.gutterSpecs = getGutters(options.gutters, options.lineNumbers);
    renderGutters(d);

    input.init(d);
}

// Since the delta values reported on mouse wheel events are
// unstandardized between browsers and even browser versions, and
// generally horribly unpredictable, this code starts by measuring
// the scroll effect that the first few mouse wheel events have,
// and, from that, detects the way it can convert deltas to pixel
// offsets afterwards.
//
// The reason we want to know the amount a wheel event will scroll
// is that it gives us a chance to update the display before the
// actual scrolling happens, reducing flickering.

var wheelSamples = 0, wheelPixelsPerUnit = null;
// Fill in a browser-detected starting value on browsers where we
// know one. These don't have to be accurate -- the result of them
// being wrong would just be a slight flicker on the first wheel
// scroll (if it is large enough).
if (ie) {
    wheelPixelsPerUnit = -.53;
} else if (gecko) {
    wheelPixelsPerUnit = 15;
} else if (chrome) {
    wheelPixelsPerUnit = -.7;
} else if (safari) {
    wheelPixelsPerUnit = -1 / 3;
}

function wheelEventDelta(e) {
    var dx = e.wheelDeltaX, dy = e.wheelDeltaY;
    if (dx == null && e.detail && e.axis == e.HORIZONTAL_AXIS) {
        dx = e.detail;
    }
    if (dy == null && e.detail && e.axis == e.VERTICAL_AXIS) {
        dy = e.detail;
    } else if (dy == null) {
        dy = e.wheelDelta;
    }
    return {x: dx, y: dy}
}

function wheelEventPixels(e) {
    var delta = wheelEventDelta(e);
    delta.x *= wheelPixelsPerUnit;
    delta.y *= wheelPixelsPerUnit;
    return delta
}

function onScrollWheel(cm, e) {
    var delta = wheelEventDelta(e), dx = delta.x, dy = delta.y;

    var display = cm.display, scroll = display.scroller;
    // Quit if there's nothing to scroll here
    var canScrollX = scroll.scrollWidth > scroll.clientWidth;
    var canScrollY = scroll.scrollHeight > scroll.clientHeight;
    if (!(dx && canScrollX || dy && canScrollY)) {
        return
    }

    // Webkit browsers on OS X abort momentum scrolls when the target
    // of the scroll event is removed from the scrollable element.
    // This hack (see related code in patchDisplay) makes sure the
    // element is kept around.
    if (dy && mac && webkit) {
        outer: for (var cur = e.target, view = display.view; cur != scroll; cur = cur.parentNode) {
            for (var i = 0; i < view.length; i++) {
                if (view[i].node == cur) {
                    cm.display.currentWheelTarget = cur;
                    break outer
                }
            }
        }
    }

    // On some browsers, horizontal scrolling will cause redraws to
    // happen before the gutter has been realigned, causing it to
    // wriggle around in a most unseemly way. When we have an
    // estimated pixels/delta value, we just handle horizontal
    // scrolling entirely here. It'll be slightly off from native, but
    // better than glitching out.
    if (dx && !gecko && !presto && wheelPixelsPerUnit != null) {
        if (dy && canScrollY) {
            updateScrollTop(cm, Math.max(0, scroll.scrollTop + dy * wheelPixelsPerUnit));
        }
        setScrollLeft(cm, Math.max(0, scroll.scrollLeft + dx * wheelPixelsPerUnit));
        // Only prevent default scrolling if vertical scrolling is
        // actually possible. Otherwise, it causes vertical scroll
        // jitter on OSX trackpads when deltaX is small and deltaY
        // is large (issue #3579)
        if (!dy || (dy && canScrollY)) {
            e_preventDefault(e);
        }
        display.wheelStartX = null; // Abort measurement, if in progress
        return
    }

    // 'Project' the visible viewport to cover the area that is being
    // scrolled into view (if we know enough to estimate it).
    if (dy && wheelPixelsPerUnit != null) {
        var pixels = dy * wheelPixelsPerUnit;
        var top = cm.doc.scrollTop, bot = top + display.wrapper.clientHeight;
        if (pixels < 0) {
            top = Math.max(0, top + pixels - 50);
        } else {
            bot = Math.min(cm.doc.height, bot + pixels + 50);
        }
        updateDisplaySimple(cm, {top: top, bottom: bot});
    }

    if (wheelSamples < 20) {
        if (display.wheelStartX == null) {
            display.wheelStartX = scroll.scrollLeft;
            display.wheelStartY = scroll.scrollTop;
            display.wheelDX = dx;
            display.wheelDY = dy;
            setTimeout(function () {
                if (display.wheelStartX == null) {
                    return
                }
                var movedX = scroll.scrollLeft - display.wheelStartX;
                var movedY = scroll.scrollTop - display.wheelStartY;
                var sample = (movedY && display.wheelDY && movedY / display.wheelDY) ||
                    (movedX && display.wheelDX && movedX / display.wheelDX);
                display.wheelStartX = display.wheelStartY = null;
                if (!sample) {
                    return
                }
                wheelPixelsPerUnit = (wheelPixelsPerUnit * wheelSamples + sample) / (wheelSamples + 1);
                ++wheelSamples;
            }, 200);
        } else {
            display.wheelDX += dx;
            display.wheelDY += dy;
        }
    }
}

// Selection objects are immutable. A new one is created every time
// the selection changes. A selection is one or more non-overlapping
// (and non-touching) ranges, sorted, and an integer that indicates
// which one is the primary selection (the one that's scrolled into
// view, that getCursor returns, etc).
var Selection = function (ranges, primIndex) {
    this.ranges = ranges;
    this.primIndex = primIndex;
};

Selection.prototype.primary = function () {
    return this.ranges[this.primIndex]
};

Selection.prototype.equals = function (other) {
    var this$1 = this;

    if (other == this) {
        return true
    }
    if (other.primIndex != this.primIndex || other.ranges.length != this.ranges.length) {
        return false
    }
    for (var i = 0; i < this.ranges.length; i++) {
        var here = this$1.ranges[i], there = other.ranges[i];
        if (!equalCursorPos(here.anchor, there.anchor) || !equalCursorPos(here.head, there.head)) {
            return false
        }
    }
    return true
};

Selection.prototype.deepCopy = function () {
    var this$1 = this;

    var out = [];
    for (var i = 0; i < this.ranges.length; i++) {
        out[i] = new Range(copyPos(this$1.ranges[i].anchor), copyPos(this$1.ranges[i].head));
    }
    return new Selection(out, this.primIndex)
};

Selection.prototype.somethingSelected = function () {
    var this$1 = this;

    for (var i = 0; i < this.ranges.length; i++) {
        if (!this$1.ranges[i].empty()) {
            return true
        }
    }
    return false
};

Selection.prototype.contains = function (pos, end) {
    var this$1 = this;

    if (!end) {
        end = pos;
    }
    for (var i = 0; i < this.ranges.length; i++) {
        var range = this$1.ranges[i];
        if (cmp(end, range.from()) >= 0 && cmp(pos, range.to()) <= 0) {
            return i
        }
    }
    return -1
};

var Range = function (anchor, head) {
    this.anchor = anchor;
    this.head = head;
};

Range.prototype.from = function () {
    return minPos(this.anchor, this.head)
};
Range.prototype.to = function () {
    return maxPos(this.anchor, this.head)
};
Range.prototype.empty = function () {
    return this.head.line == this.anchor.line && this.head.ch == this.anchor.ch
};

// Take an unsorted, potentially overlapping set of ranges, and
// build a selection out of it. 'Consumes' ranges array (modifying
// it).
function normalizeSelection(cm, ranges, primIndex) {
    var mayTouch = cm && cm.options.selectionsMayTouch;
    var prim = ranges[primIndex];
    ranges.sort(function (a, b) {
        return cmp(a.from(), b.from());
    });
    primIndex = indexOf(ranges, prim);
    for (var i = 1; i < ranges.length; i++) {
        var cur = ranges[i], prev = ranges[i - 1];
        var diff = cmp(prev.to(), cur.from());
        if (mayTouch && !cur.empty() ? diff > 0 : diff >= 0) {
            var from = minPos(prev.from(), cur.from()), to = maxPos(prev.to(), cur.to());
            var inv = prev.empty() ? cur.from() == cur.head : prev.from() == prev.head;
            if (i <= primIndex) {
                --primIndex;
            }
            ranges.splice(--i, 2, new Range(inv ? to : from, inv ? from : to));
        }
    }
    return new Selection(ranges, primIndex)
}

function simpleSelection(anchor, head) {
    return new Selection([new Range(anchor, head || anchor)], 0)
}

// Compute the position of the end of a change (its 'to' property
// refers to the pre-change end).
function changeEnd(change) {
    if (!change.text) {
        return change.to
    }
    return Pos(change.from.line + change.text.length - 1,
        lst(change.text).length + (change.text.length == 1 ? change.from.ch : 0))
}

// Adjust a position to refer to the post-change position of the
// same text, or the end of the change if the change covers it.
function adjustForChange(pos, change) {
    if (cmp(pos, change.from) < 0) {
        return pos
    }
    if (cmp(pos, change.to) <= 0) {
        return changeEnd(change)
    }

    var line = pos.line + change.text.length - (change.to.line - change.from.line) - 1, ch = pos.ch;
    if (pos.line == change.to.line) {
        ch += changeEnd(change).ch - change.to.ch;
    }
    return Pos(line, ch)
}

function computeSelAfterChange(doc, change) {
    var out = [];
    for (var i = 0; i < doc.sel.ranges.length; i++) {
        var range = doc.sel.ranges[i];
        out.push(new Range(adjustForChange(range.anchor, change),
            adjustForChange(range.head, change)));
    }
    return normalizeSelection(doc.cm, out, doc.sel.primIndex)
}

function offsetPos(pos, old, nw) {
    if (pos.line == old.line) {
        return Pos(nw.line, pos.ch - old.ch + nw.ch)
    } else {
        return Pos(nw.line + (pos.line - old.line), pos.ch)
    }
}

// Used by replaceSelections to allow moving the selection to the
// start or around the replaced test. Hint may be "start" or "around".
function computeReplacedSel(doc, changes, hint) {
    var out = [];
    var oldPrev = Pos(doc.first, 0), newPrev = oldPrev;
    for (var i = 0; i < changes.length; i++) {
        var change = changes[i];
        var from = offsetPos(change.from, oldPrev, newPrev);
        var to = offsetPos(changeEnd(change), oldPrev, newPrev);
        oldPrev = change.to;
        newPrev = to;
        if (hint == "around") {
            var range = doc.sel.ranges[i], inv = cmp(range.head, range.anchor) < 0;
            out[i] = new Range(inv ? to : from, inv ? from : to);
        } else {
            out[i] = new Range(from, from);
        }
    }
    return new Selection(out, doc.sel.primIndex)
}

// Used to get the src into a consistent state again when options change.

function loadMode(cm) {
    cm.doc.mode = getMode(cm.options, cm.doc.modeOption);
    resetModeState(cm);
}

function resetModeState(cm) {
    cm.doc.iter(function (line) {
        if (line.stateAfter) {
            line.stateAfter = null;
        }
        if (line.styles) {
            line.styles = null;
        }
    });
    cm.doc.modeFrontier = cm.doc.highlightFrontier = cm.doc.first;
    startWorker(cm, 100);
    cm.state.modeGen++;
    if (cm.curOp) {
        regChange(cm);
    }
}

// DOCUMENT DATA STRUCTURE

// By default, updates that start and end at the beginning of a line
// are treated specially, in order to make the association of line
// widgets and marker elements with the text behave more intuitive.
function isWholeLineUpdate(doc, change) {
    return change.from.ch == 0 && change.to.ch == 0 && lst(change.text) == "" &&
        (!doc.cm || doc.cm.options.wholeLineUpdateBefore)
}

// Perform a change on the document data structure.
function updateDoc(doc, change, markedSpans, estimateHeight$$1) {
    function spansFor(n) {
        return markedSpans ? markedSpans[n] : null
    }

    function update(line, text, spans) {
        updateLine(line, text, spans, estimateHeight$$1);
        signalLater(line, "change", line, change);
    }

    function linesFor(start, end) {
        var result = [];
        for (var i = start; i < end; ++i) {
            result.push(new Line(text[i], spansFor(i), estimateHeight$$1));
        }
        return result
    }

    var from = change.from, to = change.to, text = change.text;
    var firstLine = getLine(doc, from.line), lastLine = getLine(doc, to.line);
    var lastText = lst(text), lastSpans = spansFor(text.length - 1), nlines = to.line - from.line;

    // Adjust the line structure
    if (change.full) {
        doc.insert(0, linesFor(0, text.length));
        doc.remove(text.length, doc.size - text.length);
    } else if (isWholeLineUpdate(doc, change)) {
        // This is a whole-line replace. Treated specially to make
        // sure line objects move the way they are supposed to.
        var added = linesFor(0, text.length - 1);
        update(lastLine, lastLine.text, lastSpans);
        if (nlines) {
            doc.remove(from.line, nlines);
        }
        if (added.length) {
            doc.insert(from.line, added);
        }
    } else if (firstLine == lastLine) {
        if (text.length == 1) {
            update(firstLine, firstLine.text.slice(0, from.ch) + lastText + firstLine.text.slice(to.ch), lastSpans);
        } else {
            var added$1 = linesFor(1, text.length - 1);
            added$1.push(new Line(lastText + firstLine.text.slice(to.ch), lastSpans, estimateHeight$$1));
            update(firstLine, firstLine.text.slice(0, from.ch) + text[0], spansFor(0));
            doc.insert(from.line + 1, added$1);
        }
    } else if (text.length == 1) {
        update(firstLine, firstLine.text.slice(0, from.ch) + text[0] + lastLine.text.slice(to.ch), spansFor(0));
        doc.remove(from.line + 1, nlines);
    } else {
        update(firstLine, firstLine.text.slice(0, from.ch) + text[0], spansFor(0));
        update(lastLine, lastText + lastLine.text.slice(to.ch), lastSpans);
        var added$2 = linesFor(1, text.length - 1);
        if (nlines > 1) {
            doc.remove(from.line + 1, nlines - 1);
        }
        doc.insert(from.line + 1, added$2);
    }

    signalLater(doc, "change", doc, change);
}

// Call f for all linked documents.
function linkedDocs(doc, f, sharedHistOnly) {
    function propagate(doc, skip, sharedHist) {
        if (doc.linked) {
            for (var i = 0; i < doc.linked.length; ++i) {
                var rel = doc.linked[i];
                if (rel.doc == skip) {
                    continue
                }
                var shared = sharedHist && rel.sharedHist;
                if (sharedHistOnly && !shared) {
                    continue
                }
                f(rel.doc, shared);
                propagate(rel.doc, doc, shared);
            }
        }
    }

    propagate(doc, null, true);
}

// Attach a document to an src.
function attachDoc(cm, doc) {
    if (doc.cm) {
        throw new Error("This document is already in use.")
    }
    cm.doc = doc;
    doc.cm = cm;
    estimateLineHeights(cm);
    loadMode(cm);
    setDirectionClass(cm);
    if (!cm.options.lineWrapping) {
        findMaxLine(cm);
    }
    cm.options.mode = doc.modeOption;
    regChange(cm);
}

function setDirectionClass(cm) {
    (cm.doc.direction == "rtl" ? addClass : rmClass)(cm.display.lineDiv, "CodeMirror-rtl");
}

function directionChanged(cm) {
    runInOp(cm, function () {
        setDirectionClass(cm);
        regChange(cm);
    });
}

function History(startGen) {
    // Arrays of change events and selections. Doing something adds an
    // event to done and clears undo. Undoing moves events from done
    // to undone, redoing moves them in the other direction.
    this.done = [];
    this.undone = [];
    this.undoDepth = Infinity;
    // Used to track when changes can be merged into a single undo
    // event
    this.lastModTime = this.lastSelTime = 0;
    this.lastOp = this.lastSelOp = null;
    this.lastOrigin = this.lastSelOrigin = null;
    // Used by the isClean() method
    this.generation = this.maxGeneration = startGen || 1;
}

// Create a history change event from an updateDoc-style change
// object.
function historyChangeFromChange(doc, change) {
    var histChange = {from: copyPos(change.from), to: changeEnd(change), text: getBetween(doc, change.from, change.to)};
    attachLocalSpans(doc, histChange, change.from.line, change.to.line + 1);
    linkedDocs(doc, function (doc) {
        return attachLocalSpans(doc, histChange, change.from.line, change.to.line + 1);
    }, true);
    return histChange
}

// Pop all selection events off the end of a history array. Stop at
// a change event.
function clearSelectionEvents(array) {
    while (array.length) {
        var last = lst(array);
        if (last.ranges) {
            array.pop();
        } else {
            break
        }
    }
}

// Find the top change event in the history. Pop off selection
// events that are in the way.
function lastChangeEvent(hist, force) {
    if (force) {
        clearSelectionEvents(hist.done);
        return lst(hist.done)
    } else if (hist.done.length && !lst(hist.done).ranges) {
        return lst(hist.done)
    } else if (hist.done.length > 1 && !hist.done[hist.done.length - 2].ranges) {
        hist.done.pop();
        return lst(hist.done)
    }
}

// Register a change in the history. Merges changes that are within
// a single operation, or are close together with an origin that
// allows merging (starting with "+") into a single event.
function addChangeToHistory(doc, change, selAfter, opId) {
    var hist = doc.history;
    hist.undone.length = 0;
    var time = +new Date, cur;
    var last;

    if ((hist.lastOp == opId ||
        hist.lastOrigin == change.origin && change.origin &&
        ((change.origin.charAt(0) == "+" && hist.lastModTime > time - (doc.cm ? doc.cm.options.historyEventDelay : 500)) ||
            change.origin.charAt(0) == "*")) &&
        (cur = lastChangeEvent(hist, hist.lastOp == opId))) {
        // Merge this change into the last event
        last = lst(cur.changes);
        if (cmp(change.from, change.to) == 0 && cmp(change.from, last.to) == 0) {
            // Optimized case for simple insertion -- don't want to add
            // new changesets for every character typed
            last.to = changeEnd(change);
        } else {
            // Add new sub-event
            cur.changes.push(historyChangeFromChange(doc, change));
        }
    } else {
        // Can not be merged, start a new event.
        var before = lst(hist.done);
        if (!before || !before.ranges) {
            pushSelectionToHistory(doc.sel, hist.done);
        }
        cur = {
            changes: [historyChangeFromChange(doc, change)],
            generation: hist.generation
        };
        hist.done.push(cur);
        while (hist.done.length > hist.undoDepth) {
            hist.done.shift();
            if (!hist.done[0].ranges) {
                hist.done.shift();
            }
        }
    }
    hist.done.push(selAfter);
    hist.generation = ++hist.maxGeneration;
    hist.lastModTime = hist.lastSelTime = time;
    hist.lastOp = hist.lastSelOp = opId;
    hist.lastOrigin = hist.lastSelOrigin = change.origin;

    if (!last) {
        signal(doc, "historyAdded");
    }
}

function selectionEventCanBeMerged(doc, origin, prev, sel) {
    var ch = origin.charAt(0);
    return ch == "*" ||
        ch == "+" &&
        prev.ranges.length == sel.ranges.length &&
        prev.somethingSelected() == sel.somethingSelected() &&
        new Date - doc.history.lastSelTime <= (doc.cm ? doc.cm.options.historyEventDelay : 500)
}

// Called whenever the selection changes, sets the new selection as
// the pending selection in the history, and pushes the old pending
// selection into the 'done' array when it was significantly
// different (in number of selected ranges, emptiness, or time).
function addSelectionToHistory(doc, sel, opId, options) {
    var hist = doc.history, origin = options && options.origin;

    // A new event is started when the previous origin does not match
    // the current, or the origins don't allow matching. Origins
    // starting with * are always merged, those starting with + are
    // merged when similar and close together in time.
    if (opId == hist.lastSelOp ||
        (origin && hist.lastSelOrigin == origin &&
            (hist.lastModTime == hist.lastSelTime && hist.lastOrigin == origin ||
                selectionEventCanBeMerged(doc, origin, lst(hist.done), sel)))) {
        hist.done[hist.done.length - 1] = sel;
    } else {
        pushSelectionToHistory(sel, hist.done);
    }

    hist.lastSelTime = +new Date;
    hist.lastSelOrigin = origin;
    hist.lastSelOp = opId;
    if (options && options.clearRedo !== false) {
        clearSelectionEvents(hist.undone);
    }
}

function pushSelectionToHistory(sel, dest) {
    var top = lst(dest);
    if (!(top && top.ranges && top.equals(sel))) {
        dest.push(sel);
    }
}

// Used to store index span information in the history.
function attachLocalSpans(doc, change, from, to) {
    var existing = change["spans_" + doc.id], n = 0;
    doc.iter(Math.max(doc.first, from), Math.min(doc.first + doc.size, to), function (line) {
        if (line.markedSpans) {
            (existing || (existing = change["spans_" + doc.id] = {}))[n] = line.markedSpans;
        }
        ++n;
    });
}

// When un/re-doing restores text containing index spans, those
// that have been explicitly cleared should not be restored.
function removeClearedSpans(spans) {
    if (!spans) {
        return null
    }
    var out;
    for (var i = 0; i < spans.length; ++i) {
        if (spans[i].marker.explicitlyCleared) {
            if (!out) {
                out = spans.slice(0, i);
            }
        } else if (out) {
            out.push(spans[i]);
        }
    }
    return !out ? spans : out.length ? out : null
}

// Retrieve and filter the old index spans stored in a change event.
function getOldSpans(doc, change) {
    var found = change["spans_" + doc.id];
    if (!found) {
        return null
    }
    var nw = [];
    for (var i = 0; i < change.text.length; ++i) {
        nw.push(removeClearedSpans(found[i]));
    }
    return nw
}

// Used for un/re-doing changes from the history. Combines the
// result of computing the existing spans with the set of spans that
// existed in the history (so that deleting around a span and then
// undoing brings back the span).
function mergeOldSpans(doc, change) {
    var old = getOldSpans(doc, change);
    var stretched = stretchSpansOverChange(doc, change);
    if (!old) {
        return stretched
    }
    if (!stretched) {
        return old
    }

    for (var i = 0; i < old.length; ++i) {
        var oldCur = old[i], stretchCur = stretched[i];
        if (oldCur && stretchCur) {
            spans: for (var j = 0; j < stretchCur.length; ++j) {
                var span = stretchCur[j];
                for (var k = 0; k < oldCur.length; ++k) {
                    if (oldCur[k].marker == span.marker) {
                        continue spans
                    }
                }
                oldCur.push(span);
            }
        } else if (stretchCur) {
            old[i] = stretchCur;
        }
    }
    return old
}

// Used both to provide a JSON-safe object in .getHistory, and, when
// detaching a document, to split the history in two
function copyHistoryArray(events, newGroup, instantiateSel) {
    var copy = [];
    for (var i = 0; i < events.length; ++i) {
        var event = events[i];
        if (event.ranges) {
            copy.push(instantiateSel ? Selection.prototype.deepCopy.call(event) : event);
            continue
        }
        var changes = event.changes, newChanges = [];
        copy.push({changes: newChanges});
        for (var j = 0; j < changes.length; ++j) {
            var change = changes[j], m = (void 0);
            newChanges.push({from: change.from, to: change.to, text: change.text});
            if (newGroup) {
                for (var prop in change) {
                    if (m = prop.match(/^spans_(\d+)$/)) {
                        if (indexOf(newGroup, Number(m[1])) > -1) {
                            lst(newChanges)[prop] = change[prop];
                            delete change[prop];
                        }
                    }
                }
            }
        }
    }
    return copy
}

// The 'scroll' parameter given to many of these indicated whether
// the new cursor position should be scrolled into view after
// modifying the selection.

// If shift is held or the extend flag is set, extends a range to
// include a given position (and optionally a second position).
// Otherwise, simply returns the range between the given positions.
// Used for cursor motion and such.
function extendRange(range, head, other, extend) {
    if (extend) {
        var anchor = range.anchor;
        if (other) {
            var posBefore = cmp(head, anchor) < 0;
            if (posBefore != (cmp(other, anchor) < 0)) {
                anchor = head;
                head = other;
            } else if (posBefore != (cmp(head, other) < 0)) {
                head = other;
            }
        }
        return new Range(anchor, head)
    } else {
        return new Range(other || head, head)
    }
}

// Extend the primary selection range, discard the rest.
function extendSelection(doc, head, other, options, extend) {
    if (extend == null) {
        extend = doc.cm && (doc.cm.display.shift || doc.extend);
    }
    setSelection(doc, new Selection([extendRange(doc.sel.primary(), head, other, extend)], 0), options);
}

// Extend all selections (pos is an array of selections with length
// equal the number of selections)
function extendSelections(doc, heads, options) {
    var out = [];
    var extend = doc.cm && (doc.cm.display.shift || doc.extend);
    for (var i = 0; i < doc.sel.ranges.length; i++) {
        out[i] = extendRange(doc.sel.ranges[i], heads[i], null, extend);
    }
    var newSel = normalizeSelection(doc.cm, out, doc.sel.primIndex);
    setSelection(doc, newSel, options);
}

// Updates a single range in the selection.
function replaceOneSelection(doc, i, range, options) {
    var ranges = doc.sel.ranges.slice(0);
    ranges[i] = range;
    setSelection(doc, normalizeSelection(doc.cm, ranges, doc.sel.primIndex), options);
}

// Reset the selection to a single range.
function setSimpleSelection(doc, anchor, head, options) {
    setSelection(doc, simpleSelection(anchor, head), options);
}

// Give beforeSelectionChange handlers a change to influence a
// selection update.
function filterSelectionChange(doc, sel, options) {
    var obj = {
        ranges: sel.ranges,
        update: function (ranges) {
            var this$1 = this;

            this.ranges = [];
            for (var i = 0; i < ranges.length; i++) {
                this$1.ranges[i] = new Range(clipPos(doc, ranges[i].anchor),
                    clipPos(doc, ranges[i].head));
            }
        },
        origin: options && options.origin
    };
    signal(doc, "beforeSelectionChange", doc, obj);
    if (doc.cm) {
        signal(doc.cm, "beforeSelectionChange", doc.cm, obj);
    }
    if (obj.ranges != sel.ranges) {
        return normalizeSelection(doc.cm, obj.ranges, obj.ranges.length - 1)
    } else {
        return sel
    }
}

function setSelectionReplaceHistory(doc, sel, options) {
    var done = doc.history.done, last = lst(done);
    if (last && last.ranges) {
        done[done.length - 1] = sel;
        setSelectionNoUndo(doc, sel, options);
    } else {
        setSelection(doc, sel, options);
    }
}

// Set a new selection.
function setSelection(doc, sel, options) {
    setSelectionNoUndo(doc, sel, options);
    addSelectionToHistory(doc, doc.sel, doc.cm ? doc.cm.curOp.id : NaN, options);
}

function setSelectionNoUndo(doc, sel, options) {
    if (hasHandler(doc, "beforeSelectionChange") || doc.cm && hasHandler(doc.cm, "beforeSelectionChange")) {
        sel = filterSelectionChange(doc, sel, options);
    }

    var bias = options && options.bias ||
        (cmp(sel.primary().head, doc.sel.primary().head) < 0 ? -1 : 1);
    setSelectionInner(doc, skipAtomicInSelection(doc, sel, bias, true));

    if (!(options && options.scroll === false) && doc.cm) {
        ensureCursorVisible(doc.cm);
    }
}

function setSelectionInner(doc, sel) {
    if (sel.equals(doc.sel)) {
        return
    }

    doc.sel = sel;

    if (doc.cm) {
        doc.cm.curOp.updateInput = 1;
        doc.cm.curOp.selectionChanged = true;
        signalCursorActivity(doc.cm);
    }
    signalLater(doc, "cursorActivity", doc);
}

// Verify that the selection does not partially select any atomic
// index ranges.
function reCheckSelection(doc) {
    setSelectionInner(doc, skipAtomicInSelection(doc, doc.sel, null, false));
}

// Return a selection that does not partially select any atomic
// ranges.
function skipAtomicInSelection(doc, sel, bias, mayClear) {
    var out;
    for (var i = 0; i < sel.ranges.length; i++) {
        var range = sel.ranges[i];
        var old = sel.ranges.length == doc.sel.ranges.length && doc.sel.ranges[i];
        var newAnchor = skipAtomic(doc, range.anchor, old && old.anchor, bias, mayClear);
        var newHead = skipAtomic(doc, range.head, old && old.head, bias, mayClear);
        if (out || newAnchor != range.anchor || newHead != range.head) {
            if (!out) {
                out = sel.ranges.slice(0, i);
            }
            out[i] = new Range(newAnchor, newHead);
        }
    }
    return out ? normalizeSelection(doc.cm, out, sel.primIndex) : sel
}

function skipAtomicInner(doc, pos, oldPos, dir, mayClear) {
    var line = getLine(doc, pos.line);
    if (line.markedSpans) {
        for (var i = 0; i < line.markedSpans.length; ++i) {
            var sp = line.markedSpans[i], m = sp.marker;

            // Determine if we should prevent the cursor being placed to the left/right of an atomic marker
            // Historically this was determined using the inclusiveLeft/Right option, but the new way to control it
            // is with selectLeft/Right
            var preventCursorLeft = ("selectLeft" in m) ? !m.selectLeft : m.inclusiveLeft;
            var preventCursorRight = ("selectRight" in m) ? !m.selectRight : m.inclusiveRight;

            if ((sp.from == null || (preventCursorLeft ? sp.from <= pos.ch : sp.from < pos.ch)) &&
                (sp.to == null || (preventCursorRight ? sp.to >= pos.ch : sp.to > pos.ch))) {
                if (mayClear) {
                    signal(m, "beforeCursorEnter");
                    if (m.explicitlyCleared) {
                        if (!line.markedSpans) {
                            break
                        } else {
                            --i;
                            continue
                        }
                    }
                }
                if (!m.atomic) {
                    continue
                }

                if (oldPos) {
                    var near = m.find(dir < 0 ? 1 : -1), diff = (void 0);
                    if (dir < 0 ? preventCursorRight : preventCursorLeft) {
                        near = movePos(doc, near, -dir, near && near.line == pos.line ? line : null);
                    }
                    if (near && near.line == pos.line && (diff = cmp(near, oldPos)) && (dir < 0 ? diff < 0 : diff > 0)) {
                        return skipAtomicInner(doc, near, pos, dir, mayClear)
                    }
                }

                var far = m.find(dir < 0 ? -1 : 1);
                if (dir < 0 ? preventCursorLeft : preventCursorRight) {
                    far = movePos(doc, far, dir, far.line == pos.line ? line : null);
                }
                return far ? skipAtomicInner(doc, far, pos, dir, mayClear) : null
            }
        }
    }
    return pos
}

// Ensure a given position is not inside an atomic range.
function skipAtomic(doc, pos, oldPos, bias, mayClear) {
    var dir = bias || 1;
    var found = skipAtomicInner(doc, pos, oldPos, dir, mayClear) ||
        (!mayClear && skipAtomicInner(doc, pos, oldPos, dir, true)) ||
        skipAtomicInner(doc, pos, oldPos, -dir, mayClear) ||
        (!mayClear && skipAtomicInner(doc, pos, oldPos, -dir, true));
    if (!found) {
        doc.cantEdit = true;
        return Pos(doc.first, 0)
    }
    return found
}

function movePos(doc, pos, dir, line) {
    if (dir < 0 && pos.ch == 0) {
        if (pos.line > doc.first) {
            return clipPos(doc, Pos(pos.line - 1))
        } else {
            return null
        }
    } else if (dir > 0 && pos.ch == (line || getLine(doc, pos.line)).text.length) {
        if (pos.line < doc.first + doc.size - 1) {
            return Pos(pos.line + 1, 0)
        } else {
            return null
        }
    } else {
        return new Pos(pos.line, pos.ch + dir)
    }
}

function selectAll(cm) {
    cm.setSelection(Pos(cm.firstLine(), 0), Pos(cm.lastLine()), sel_dontScroll);
}

// UPDATING

// Allow "beforeChange" event handlers to influence a change
function filterChange(doc, change, update) {
    var obj = {
        canceled: false,
        from: change.from,
        to: change.to,
        text: change.text,
        origin: change.origin,
        cancel: function () {
            return obj.canceled = true;
        }
    };
    if (update) {
        obj.update = function (from, to, text, origin) {
            if (from) {
                obj.from = clipPos(doc, from);
            }
            if (to) {
                obj.to = clipPos(doc, to);
            }
            if (text) {
                obj.text = text;
            }
            if (origin !== undefined) {
                obj.origin = origin;
            }
        };
    }
    signal(doc, "beforeChange", doc, obj);
    if (doc.cm) {
        signal(doc.cm, "beforeChange", doc.cm, obj);
    }

    if (obj.canceled) {
        if (doc.cm) {
            doc.cm.curOp.updateInput = 2;
        }
        return null
    }
    return {from: obj.from, to: obj.to, text: obj.text, origin: obj.origin}
}

// Apply a change to a document, and add it to the document's
// history, and propagating it to all linked documents.
function makeChange(doc, change, ignoreReadOnly) {
    if (doc.cm) {
        if (!doc.cm.curOp) {
            return operation(doc.cm, makeChange)(doc, change, ignoreReadOnly)
        }
        if (doc.cm.state.suppressEdits) {
            return
        }
    }

    if (hasHandler(doc, "beforeChange") || doc.cm && hasHandler(doc.cm, "beforeChange")) {
        change = filterChange(doc, change, true);
        if (!change) {
            return
        }
    }

    // Possibly split or suppress the update based on the presence
    // of read-only spans in its range.
    var split = sawReadOnlySpans && !ignoreReadOnly && removeReadOnlyRanges(doc, change.from, change.to);
    if (split) {
        for (var i = split.length - 1; i >= 0; --i) {
            makeChangeInner(doc, {
                from: split[i].from,
                to: split[i].to,
                text: i ? [""] : change.text,
                origin: change.origin
            });
        }
    } else {
        makeChangeInner(doc, change);
    }
}

function makeChangeInner(doc, change) {
    if (change.text.length == 1 && change.text[0] == "" && cmp(change.from, change.to) == 0) {
        return
    }
    var selAfter = computeSelAfterChange(doc, change);
    addChangeToHistory(doc, change, selAfter, doc.cm ? doc.cm.curOp.id : NaN);

    makeChangeSingleDoc(doc, change, selAfter, stretchSpansOverChange(doc, change));
    var rebased = [];

    linkedDocs(doc, function (doc, sharedHist) {
        if (!sharedHist && indexOf(rebased, doc.history) == -1) {
            rebaseHist(doc.history, change);
            rebased.push(doc.history);
        }
        makeChangeSingleDoc(doc, change, null, stretchSpansOverChange(doc, change));
    });
}

// Revert a change stored in a document's history.
function makeChangeFromHistory(doc, type, allowSelectionOnly) {
    var suppress = doc.cm && doc.cm.state.suppressEdits;
    if (suppress && !allowSelectionOnly) {
        return
    }

    var hist = doc.history, event, selAfter = doc.sel;
    var source = type == "undo" ? hist.done : hist.undone, dest = type == "undo" ? hist.undone : hist.done;

    // Verify that there is a useable event (so that ctrl-z won't
    // needlessly clear selection events)
    var i = 0;
    for (; i < source.length; i++) {
        event = source[i];
        if (allowSelectionOnly ? event.ranges && !event.equals(doc.sel) : !event.ranges) {
            break
        }
    }
    if (i == source.length) {
        return
    }
    hist.lastOrigin = hist.lastSelOrigin = null;

    for (; ;) {
        event = source.pop();
        if (event.ranges) {
            pushSelectionToHistory(event, dest);
            if (allowSelectionOnly && !event.equals(doc.sel)) {
                setSelection(doc, event, {clearRedo: false});
                return
            }
            selAfter = event;
        } else if (suppress) {
            source.push(event);
            return
        } else {
            break
        }
    }

    // Build up a reverse change object to add to the opposite history
    // stack (redo when undoing, and vice versa).
    var antiChanges = [];
    pushSelectionToHistory(selAfter, dest);
    dest.push({changes: antiChanges, generation: hist.generation});
    hist.generation = event.generation || ++hist.maxGeneration;

    var filter = hasHandler(doc, "beforeChange") || doc.cm && hasHandler(doc.cm, "beforeChange");

    var loop = function (i) {
        var change = event.changes[i];
        change.origin = type;
        if (filter && !filterChange(doc, change, false)) {
            source.length = 0;
            return {}
        }

        antiChanges.push(historyChangeFromChange(doc, change));

        var after = i ? computeSelAfterChange(doc, change) : lst(source);
        makeChangeSingleDoc(doc, change, after, mergeOldSpans(doc, change));
        if (!i && doc.cm) {
            doc.cm.scrollIntoView({from: change.from, to: changeEnd(change)});
        }
        var rebased = [];

        // Propagate to the linked documents
        linkedDocs(doc, function (doc, sharedHist) {
            if (!sharedHist && indexOf(rebased, doc.history) == -1) {
                rebaseHist(doc.history, change);
                rebased.push(doc.history);
            }
            makeChangeSingleDoc(doc, change, null, mergeOldSpans(doc, change));
        });
    };

    for (var i$1 = event.changes.length - 1; i$1 >= 0; --i$1) {
        var returned = loop(i$1);

        if (returned) return returned.v;
    }
}

// Sub-views need their line numbers shifted when text is added
// above or below them in the parent document.
function shiftDoc(doc, distance) {
    if (distance == 0) {
        return
    }
    doc.first += distance;
    doc.sel = new Selection(map(doc.sel.ranges, function (range) {
        return new Range(
            Pos(range.anchor.line + distance, range.anchor.ch),
            Pos(range.head.line + distance, range.head.ch)
        );
    }), doc.sel.primIndex);
    if (doc.cm) {
        regChange(doc.cm, doc.first, doc.first - distance, distance);
        for (var d = doc.cm.display, l = d.viewFrom; l < d.viewTo; l++) {
            regLineChange(doc.cm, l, "gutter");
        }
    }
}

// More lower-level change function, handling only a single document
// (not linked ones).
function makeChangeSingleDoc(doc, change, selAfter, spans) {
    if (doc.cm && !doc.cm.curOp) {
        return operation(doc.cm, makeChangeSingleDoc)(doc, change, selAfter, spans)
    }

    if (change.to.line < doc.first) {
        shiftDoc(doc, change.text.length - 1 - (change.to.line - change.from.line));
        return
    }
    if (change.from.line > doc.lastLine()) {
        return
    }

    // Clip the change to the size of this docs
    if (change.from.line < doc.first) {
        var shift = change.text.length - 1 - (doc.first - change.from.line);
        shiftDoc(doc, shift);
        change = {
            from: Pos(doc.first, 0), to: Pos(change.to.line + shift, change.to.ch),
            text: [lst(change.text)], origin: change.origin
        };
    }
    var last = doc.lastLine();
    if (change.to.line > last) {
        change = {
            from: change.from, to: Pos(last, getLine(doc, last).text.length),
            text: [change.text[0]], origin: change.origin
        };
    }

    change.removed = getBetween(doc, change.from, change.to);

    if (!selAfter) {
        selAfter = computeSelAfterChange(doc, change);
    }
    if (doc.cm) {
        makeChangeSingleDocInEditor(doc.cm, change, spans);
    } else {
        updateDoc(doc, change, spans);
    }
    setSelectionNoUndo(doc, selAfter, sel_dontScroll);

    if (doc.cantEdit && skipAtomic(doc, Pos(doc.firstLine(), 0))) {
        doc.cantEdit = false;
    }
}

// Handle the interaction of a change to a document with the src
// that this document is part of.
function makeChangeSingleDocInEditor(cm, change, spans) {
    var doc = cm.doc, display = cm.display, from = change.from, to = change.to;

    var recomputeMaxLength = false, checkWidthStart = from.line;
    if (!cm.options.lineWrapping) {
        checkWidthStart = lineNo(visualLine(getLine(doc, from.line)));
        doc.iter(checkWidthStart, to.line + 1, function (line) {
            if (line == display.maxLine) {
                recomputeMaxLength = true;
                return true
            }
        });
    }

    if (doc.sel.contains(change.from, change.to) > -1) {
        signalCursorActivity(cm);
    }

    updateDoc(doc, change, spans, estimateHeight(cm));

    if (!cm.options.lineWrapping) {
        doc.iter(checkWidthStart, from.line + change.text.length, function (line) {
            var len = lineLength(line);
            if (len > display.maxLineLength) {
                display.maxLine = line;
                display.maxLineLength = len;
                display.maxLineChanged = true;
                recomputeMaxLength = false;
            }
        });
        if (recomputeMaxLength) {
            cm.curOp.updateMaxLine = true;
        }
    }

    retreatFrontier(doc, from.line);
    startWorker(cm, 400);

    var lendiff = change.text.length - (to.line - from.line) - 1;
    // Remember that these lines changed, for updating the display
    if (change.full) {
        regChange(cm);
    } else if (from.line == to.line && change.text.length == 1 && !isWholeLineUpdate(cm.doc, change)) {
        regLineChange(cm, from.line, "text");
    } else {
        regChange(cm, from.line, to.line + 1, lendiff);
    }

    var changesHandler = hasHandler(cm, "changes"), changeHandler = hasHandler(cm, "change");
    if (changeHandler || changesHandler) {
        var obj = {
            from: from, to: to,
            text: change.text,
            removed: change.removed,
            origin: change.origin
        };
        if (changeHandler) {
            signalLater(cm, "change", cm, obj);
        }
        if (changesHandler) {
            (cm.curOp.changeObjs || (cm.curOp.changeObjs = [])).push(obj);
        }
    }
    cm.display.selForContextMenu = null;
}

function replaceRange(doc, code, from, to, origin) {
    var assign;

    if (!to) {
        to = from;
    }
    if (cmp(to, from) < 0) {
        (assign = [to, from], from = assign[0], to = assign[1]);
    }
    if (typeof code == "string") {
        code = doc.splitLines(code);
    }
    makeChange(doc, {from: from, to: to, text: code, origin: origin});
}

// Rebasing/resetting history to deal with externally-sourced changes

function rebaseHistSelSingle(pos, from, to, diff) {
    if (to < pos.line) {
        pos.line += diff;
    } else if (from < pos.line) {
        pos.line = from;
        pos.ch = 0;
    }
}

// Tries to rebase an array of history events given a change in the
// document. If the change touches the same lines as the event, the
// event, and everything 'behind' it, is discarded. If the change is
// before the event, the event's positions are updated. Uses a
// copy-on-write scheme for the positions, to avoid having to
// reallocate them all on every rebase, but also avoid problems with
// shared position objects being unsafely updated.
function rebaseHistArray(array, from, to, diff) {
    for (var i = 0; i < array.length; ++i) {
        var sub = array[i], ok = true;
        if (sub.ranges) {
            if (!sub.copied) {
                sub = array[i] = sub.deepCopy();
                sub.copied = true;
            }
            for (var j = 0; j < sub.ranges.length; j++) {
                rebaseHistSelSingle(sub.ranges[j].anchor, from, to, diff);
                rebaseHistSelSingle(sub.ranges[j].head, from, to, diff);
            }
            continue
        }
        for (var j$1 = 0; j$1 < sub.changes.length; ++j$1) {
            var cur = sub.changes[j$1];
            if (to < cur.from.line) {
                cur.from = Pos(cur.from.line + diff, cur.from.ch);
                cur.to = Pos(cur.to.line + diff, cur.to.ch);
            } else if (from <= cur.to.line) {
                ok = false;
                break
            }
        }
        if (!ok) {
            array.splice(0, i + 1);
            i = 0;
        }
    }
}

function rebaseHist(hist, change) {
    var from = change.from.line, to = change.to.line, diff = change.text.length - (to - from) - 1;
    rebaseHistArray(hist.done, from, to, diff);
    rebaseHistArray(hist.undone, from, to, diff);
}

// Utility for applying a change to a line by handle or number,
// returning the number and optionally registering the line as
// changed.
function changeLine(doc, handle, changeType, op) {
    var no = handle, line = handle;
    if (typeof handle == "number") {
        line = getLine(doc, clipLine(doc, handle));
    } else {
        no = lineNo(handle);
    }
    if (no == null) {
        return null
    }
    if (op(line, no) && doc.cm) {
        regLineChange(doc.cm, no, changeType);
    }
    return line
}

// The document is represented as a BTree consisting of leaves, with
// chunk of lines in them, and branches, with up to ten leaves or
// other branch nodes below them. The top node is always a branch
// node, and is the document object itself (meaning it has
// additional methods and properties).
//
// All nodes have parent links. The tree is used both to go from
// line numbers to line objects, and to go from objects to numbers.
// It also indexes by height, and is used to convert between height
// and line object, and to find the total height of the document.
//
// See also http://marijnhaverbeke.nl/blog/codemirror-line-tree.html

function LeafChunk(lines) {
    var this$1 = this;

    this.lines = lines;
    this.parent = null;
    var height = 0;
    for (var i = 0; i < lines.length; ++i) {
        lines[i].parent = this$1;
        height += lines[i].height;
    }
    this.height = height;
}

LeafChunk.prototype = {
    chunkSize: function () {
        return this.lines.length
    },

    // Remove the n lines at offset 'at'.
    removeInner: function (at, n) {
        var this$1 = this;

        for (var i = at, e = at + n; i < e; ++i) {
            var line = this$1.lines[i];
            this$1.height -= line.height;
            cleanUpLine(line);
            signalLater(line, "delete");
        }
        this.lines.splice(at, n);
    },

    // Helper used to collapse a small branch into a single leaf.
    collapse: function (lines) {
        lines.push.apply(lines, this.lines);
    },

    // Insert the given array of lines at offset 'at', count them as
    // having the given height.
    insertInner: function (at, lines, height) {
        var this$1 = this;

        this.height += height;
        this.lines = this.lines.slice(0, at).concat(lines).concat(this.lines.slice(at));
        for (var i = 0; i < lines.length; ++i) {
            lines[i].parent = this$1;
        }
    },

    // Used to iterate over a part of the tree.
    iterN: function (at, n, op) {
        var this$1 = this;

        for (var e = at + n; at < e; ++at) {
            if (op(this$1.lines[at])) {
                return true
            }
        }
    }
};

function BranchChunk(children) {
    var this$1 = this;

    this.children = children;
    var size = 0, height = 0;
    for (var i = 0; i < children.length; ++i) {
        var ch = children[i];
        size += ch.chunkSize();
        height += ch.height;
        ch.parent = this$1;
    }
    this.size = size;
    this.height = height;
    this.parent = null;
}

BranchChunk.prototype = {
    chunkSize: function () {
        return this.size
    },

    removeInner: function (at, n) {
        var this$1 = this;

        this.size -= n;
        for (var i = 0; i < this.children.length; ++i) {
            var child = this$1.children[i], sz = child.chunkSize();
            if (at < sz) {
                var rm = Math.min(n, sz - at), oldHeight = child.height;
                child.removeInner(at, rm);
                this$1.height -= oldHeight - child.height;
                if (sz == rm) {
                    this$1.children.splice(i--, 1);
                    child.parent = null;
                }
                if ((n -= rm) == 0) {
                    break
                }
                at = 0;
            } else {
                at -= sz;
            }
        }
        // If the result is smaller than 25 lines, ensure that it is a
        // single leaf node.
        if (this.size - n < 25 &&
            (this.children.length > 1 || !(this.children[0] instanceof LeafChunk))) {
            var lines = [];
            this.collapse(lines);
            this.children = [new LeafChunk(lines)];
            this.children[0].parent = this;
        }
    },

    collapse: function (lines) {
        var this$1 = this;

        for (var i = 0; i < this.children.length; ++i) {
            this$1.children[i].collapse(lines);
        }
    },

    insertInner: function (at, lines, height) {
        var this$1 = this;

        this.size += lines.length;
        this.height += height;
        for (var i = 0; i < this.children.length; ++i) {
            var child = this$1.children[i], sz = child.chunkSize();
            if (at <= sz) {
                child.insertInner(at, lines, height);
                if (child.lines && child.lines.length > 50) {
                    // To avoid memory thrashing when child.lines is huge (e.g. first view of a large file), it's never spliced.
                    // Instead, small slices are taken. They're taken in order because sequential memory accesses are fastest.
                    var remaining = child.lines.length % 25 + 25;
                    for (var pos = remaining; pos < child.lines.length;) {
                        var leaf = new LeafChunk(child.lines.slice(pos, pos += 25));
                        child.height -= leaf.height;
                        this$1.children.splice(++i, 0, leaf);
                        leaf.parent = this$1;
                    }
                    child.lines = child.lines.slice(0, remaining);
                    this$1.maybeSpill();
                }
                break
            }
            at -= sz;
        }
    },

    // When a node has grown, check whether it should be split.
    maybeSpill: function () {
        if (this.children.length <= 10) {
            return
        }
        var me = this;
        do {
            var spilled = me.children.splice(me.children.length - 5, 5);
            var sibling = new BranchChunk(spilled);
            if (!me.parent) { // Become the parent node
                var copy = new BranchChunk(me.children);
                copy.parent = me;
                me.children = [copy, sibling];
                me = copy;
            } else {
                me.size -= sibling.size;
                me.height -= sibling.height;
                var myIndex = indexOf(me.parent.children, me);
                me.parent.children.splice(myIndex + 1, 0, sibling);
            }
            sibling.parent = me.parent;
        } while (me.children.length > 10)
        me.parent.maybeSpill();
    },

    iterN: function (at, n, op) {
        var this$1 = this;

        for (var i = 0; i < this.children.length; ++i) {
            var child = this$1.children[i], sz = child.chunkSize();
            if (at < sz) {
                var used = Math.min(n, sz - at);
                if (child.iterN(at, used, op)) {
                    return true
                }
                if ((n -= used) == 0) {
                    break
                }
                at = 0;
            } else {
                at -= sz;
            }
        }
    }
};

// Line widgets are block elements displayed above or below a line.

var LineWidget = function (doc, node, options) {
    var this$1 = this;

    if (options) {
        for (var opt in options) {
            if (options.hasOwnProperty(opt)) {
                this$1[opt] = options[opt];
            }
        }
    }
    this.doc = doc;
    this.node = node;
};

LineWidget.prototype.clear = function () {
    var this$1 = this;

    var cm = this.doc.cm, ws = this.line.widgets, line = this.line, no = lineNo(line);
    if (no == null || !ws) {
        return
    }
    for (var i = 0; i < ws.length; ++i) {
        if (ws[i] == this$1) {
            ws.splice(i--, 1);
        }
    }
    if (!ws.length) {
        line.widgets = null;
    }
    var height = widgetHeight(this);
    updateLineHeight(line, Math.max(0, line.height - height));
    if (cm) {
        runInOp(cm, function () {
            adjustScrollWhenAboveVisible(cm, line, -height);
            regLineChange(cm, no, "widget");
        });
        signalLater(cm, "lineWidgetCleared", cm, this, no);
    }
};

LineWidget.prototype.changed = function () {
    var this$1 = this;

    var oldH = this.height, cm = this.doc.cm, line = this.line;
    this.height = null;
    var diff = widgetHeight(this) - oldH;
    if (!diff) {
        return
    }
    if (!lineIsHidden(this.doc, line)) {
        updateLineHeight(line, line.height + diff);
    }
    if (cm) {
        runInOp(cm, function () {
            cm.curOp.forceUpdate = true;
            adjustScrollWhenAboveVisible(cm, line, diff);
            signalLater(cm, "lineWidgetChanged", cm, this$1, lineNo(line));
        });
    }
};
eventMixin(LineWidget);

function adjustScrollWhenAboveVisible(cm, line, diff) {
    if (heightAtLine(line) < ((cm.curOp && cm.curOp.scrollTop) || cm.doc.scrollTop)) {
        addToScrollTop(cm, diff);
    }
}

function addLineWidget(doc, handle, node, options) {
    var widget = new LineWidget(doc, node, options);
    var cm = doc.cm;
    if (cm && widget.noHScroll) {
        cm.display.alignWidgets = true;
    }
    changeLine(doc, handle, "widget", function (line) {
        var widgets = line.widgets || (line.widgets = []);
        if (widget.insertAt == null) {
            widgets.push(widget);
        } else {
            widgets.splice(Math.min(widgets.length - 1, Math.max(0, widget.insertAt)), 0, widget);
        }
        widget.line = line;
        if (cm && !lineIsHidden(doc, line)) {
            var aboveVisible = heightAtLine(line) < doc.scrollTop;
            updateLineHeight(line, line.height + widgetHeight(widget));
            if (aboveVisible) {
                addToScrollTop(cm, widget.height);
            }
            cm.curOp.forceUpdate = true;
        }
        return true
    });
    if (cm) {
        signalLater(cm, "lineWidgetAdded", cm, widget, typeof handle == "number" ? handle : lineNo(handle));
    }
    return widget
}

var nextMarkerId = 0;

var TextMarker = function (doc, type) {
    this.lines = [];
    this.type = type;
    this.doc = doc;
    this.id = ++nextMarkerId;
};

// Clear the marker.
TextMarker.prototype.clear = function () {
    var this$1 = this;

    if (this.explicitlyCleared) {
        return
    }
    var cm = this.doc.cm, withOp = cm && !cm.curOp;
    if (withOp) {
        startOperation(cm);
    }
    if (hasHandler(this, "clear")) {
        var found = this.find();
        if (found) {
            signalLater(this, "clear", found.from, found.to);
        }
    }
    var min = null, max = null;
    for (var i = 0; i < this.lines.length; ++i) {
        var line = this$1.lines[i];
        var span = getMarkedSpanFor(line.markedSpans, this$1);
        if (cm && !this$1.collapsed) {
            regLineChange(cm, lineNo(line), "text");
        } else if (cm) {
            if (span.to != null) {
                max = lineNo(line);
            }
            if (span.from != null) {
                min = lineNo(line);
            }
        }
        line.markedSpans = removeMarkedSpan(line.markedSpans, span);
        if (span.from == null && this$1.collapsed && !lineIsHidden(this$1.doc, line) && cm) {
            updateLineHeight(line, textHeight(cm.display));
        }
    }
    if (cm && this.collapsed && !cm.options.lineWrapping) {
        for (var i$1 = 0; i$1 < this.lines.length; ++i$1) {
            var visual = visualLine(this$1.lines[i$1]), len = lineLength(visual);
            if (len > cm.display.maxLineLength) {
                cm.display.maxLine = visual;
                cm.display.maxLineLength = len;
                cm.display.maxLineChanged = true;
            }
        }
    }

    if (min != null && cm && this.collapsed) {
        regChange(cm, min, max + 1);
    }
    this.lines.length = 0;
    this.explicitlyCleared = true;
    if (this.atomic && this.doc.cantEdit) {
        this.doc.cantEdit = false;
        if (cm) {
            reCheckSelection(cm.doc);
        }
    }
    if (cm) {
        signalLater(cm, "markerCleared", cm, this, min, max);
    }
    if (withOp) {
        endOperation(cm);
    }
    if (this.parent) {
        this.parent.clear();
    }
};

// Find the position of the marker in the document. Returns a {from,
// to} object by default. Side can be passed to get a specific side
// -- 0 (both), -1 (left), or 1 (right). When lineObj is true, the
// Pos objects returned contain a line object, rather than a line
// number (used to prevent looking up the same line twice).
TextMarker.prototype.find = function (side, lineObj) {
    var this$1 = this;

    if (side == null && this.type == "bookmark") {
        side = 1;
    }
    var from, to;
    for (var i = 0; i < this.lines.length; ++i) {
        var line = this$1.lines[i];
        var span = getMarkedSpanFor(line.markedSpans, this$1);
        if (span.from != null) {
            from = Pos(lineObj ? line : lineNo(line), span.from);
            if (side == -1) {
                return from
            }
        }
        if (span.to != null) {
            to = Pos(lineObj ? line : lineNo(line), span.to);
            if (side == 1) {
                return to
            }
        }
    }
    return from && {from: from, to: to}
};

// Signals that the marker's widget changed, and surrounding layout
// should be recomputed.
TextMarker.prototype.changed = function () {
    var this$1 = this;

    var pos = this.find(-1, true), widget = this, cm = this.doc.cm;
    if (!pos || !cm) {
        return
    }
    runInOp(cm, function () {
        var line = pos.line, lineN = lineNo(pos.line);
        var view = findViewForLine(cm, lineN);
        if (view) {
            clearLineMeasurementCacheFor(view);
            cm.curOp.selectionChanged = cm.curOp.forceUpdate = true;
        }
        cm.curOp.updateMaxLine = true;
        if (!lineIsHidden(widget.doc, line) && widget.height != null) {
            var oldHeight = widget.height;
            widget.height = null;
            var dHeight = widgetHeight(widget) - oldHeight;
            if (dHeight) {
                updateLineHeight(line, line.height + dHeight);
            }
        }
        signalLater(cm, "markerChanged", cm, this$1);
    });
};

TextMarker.prototype.attachLine = function (line) {
    if (!this.lines.length && this.doc.cm) {
        var op = this.doc.cm.curOp;
        if (!op.maybeHiddenMarkers || indexOf(op.maybeHiddenMarkers, this) == -1) {
            (op.maybeUnhiddenMarkers || (op.maybeUnhiddenMarkers = [])).push(this);
        }
    }
    this.lines.push(line);
};

TextMarker.prototype.detachLine = function (line) {
    this.lines.splice(indexOf(this.lines, line), 1);
    if (!this.lines.length && this.doc.cm) {
        var op = this.doc.cm.curOp
        ;(op.maybeHiddenMarkers || (op.maybeHiddenMarkers = [])).push(this);
    }
};
eventMixin(TextMarker);

// Create a marker, wire it up to the right lines, and
function markText(doc, from, to, options, type) {
    // Shared markers (across linked documents) are handled separately
    // (markTextShared will call out to this again, once per
    // document).
    if (options && options.shared) {
        return markTextShared(doc, from, to, options, type)
    }
    // Ensure we are in an operation.
    if (doc.cm && !doc.cm.curOp) {
        return operation(doc.cm, markText)(doc, from, to, options, type)
    }

    var marker = new TextMarker(doc, type), diff = cmp(from, to);
    if (options) {
        copyObj(options, marker, false);
    }
    // Don't connect empty markers unless clearWhenEmpty is false
    if (diff > 0 || diff == 0 && marker.clearWhenEmpty !== false) {
        return marker
    }
    if (marker.replacedWith) {
        // Showing up as a widget implies collapsed (widget replaces text)
        marker.collapsed = true;
        marker.widgetNode = eltP("span", [marker.replacedWith], "CodeMirror-widget");
        if (!options.handleMouseEvents) {
            marker.widgetNode.setAttribute("cm-ignore-events", "true");
        }
        if (options.insertLeft) {
            marker.widgetNode.insertLeft = true;
        }
    }
    if (marker.collapsed) {
        if (conflictingCollapsedRange(doc, from.line, from, to, marker) ||
            from.line != to.line && conflictingCollapsedRange(doc, to.line, from, to, marker)) {
            throw new Error("Inserting collapsed marker partially overlapping an existing one")
        }
        seeCollapsedSpans();
    }

    if (marker.addToHistory) {
        addChangeToHistory(doc, {from: from, to: to, origin: "markText"}, doc.sel, NaN);
    }

    var curLine = from.line, cm = doc.cm, updateMaxLine;
    doc.iter(curLine, to.line + 1, function (line) {
        if (cm && marker.collapsed && !cm.options.lineWrapping && visualLine(line) == cm.display.maxLine) {
            updateMaxLine = true;
        }
        if (marker.collapsed && curLine != from.line) {
            updateLineHeight(line, 0);
        }
        addMarkedSpan(line, new MarkedSpan(marker,
            curLine == from.line ? from.ch : null,
            curLine == to.line ? to.ch : null));
        ++curLine;
    });
    // lineIsHidden depends on the presence of the spans, so needs a second pass
    if (marker.collapsed) {
        doc.iter(from.line, to.line + 1, function (line) {
            if (lineIsHidden(doc, line)) {
                updateLineHeight(line, 0);
            }
        });
    }

    if (marker.clearOnEnter) {
        on(marker, "beforeCursorEnter", function () {
            return marker.clear();
        });
    }

    if (marker.readOnly) {
        seeReadOnlySpans();
        if (doc.history.done.length || doc.history.undone.length) {
            doc.clearHistory();
        }
    }
    if (marker.collapsed) {
        marker.id = ++nextMarkerId;
        marker.atomic = true;
    }
    if (cm) {
        // Sync src state
        if (updateMaxLine) {
            cm.curOp.updateMaxLine = true;
        }
        if (marker.collapsed) {
            regChange(cm, from.line, to.line + 1);
        } else if (marker.className || marker.startStyle || marker.endStyle || marker.css ||
            marker.attributes || marker.title) {
            for (var i = from.line; i <= to.line; i++) {
                regLineChange(cm, i, "text");
            }
        }
        if (marker.atomic) {
            reCheckSelection(cm.doc);
        }
        signalLater(cm, "markerAdded", cm, marker);
    }
    return marker
}

// SHARED TEXTMARKERS

// A shared marker spans multiple linked documents. It is
// implemented as a meta-marker-object controlling multiple normal
// markers.
var SharedTextMarker = function (markers, primary) {
    var this$1 = this;

    this.markers = markers;
    this.primary = primary;
    for (var i = 0; i < markers.length; ++i) {
        markers[i].parent = this$1;
    }
};

SharedTextMarker.prototype.clear = function () {
    var this$1 = this;

    if (this.explicitlyCleared) {
        return
    }
    this.explicitlyCleared = true;
    for (var i = 0; i < this.markers.length; ++i) {
        this$1.markers[i].clear();
    }
    signalLater(this, "clear");
};

SharedTextMarker.prototype.find = function (side, lineObj) {
    return this.primary.find(side, lineObj)
};
eventMixin(SharedTextMarker);

function markTextShared(doc, from, to, options, type) {
    options = copyObj(options);
    options.shared = false;
    var markers = [markText(doc, from, to, options, type)], primary = markers[0];
    var widget = options.widgetNode;
    linkedDocs(doc, function (doc) {
        if (widget) {
            options.widgetNode = widget.cloneNode(true);
        }
        markers.push(markText(doc, clipPos(doc, from), clipPos(doc, to), options, type));
        for (var i = 0; i < doc.linked.length; ++i) {
            if (doc.linked[i].isParent) {
                return
            }
        }
        primary = lst(markers);
    });
    return new SharedTextMarker(markers, primary)
}

function findSharedMarkers(doc) {
    return doc.findMarks(Pos(doc.first, 0), doc.clipPos(Pos(doc.lastLine())), function (m) {
        return m.parent;
    })
}

function copySharedMarkers(doc, markers) {
    for (var i = 0; i < markers.length; i++) {
        var marker = markers[i], pos = marker.find();
        var mFrom = doc.clipPos(pos.from), mTo = doc.clipPos(pos.to);
        if (cmp(mFrom, mTo)) {
            var subMark = markText(doc, mFrom, mTo, marker.primary, marker.primary.type);
            marker.markers.push(subMark);
            subMark.parent = marker;
        }
    }
}

function detachSharedMarkers(markers) {
    var loop = function (i) {
        var marker = markers[i], linked = [marker.primary.doc];
        linkedDocs(marker.primary.doc, function (d) {
            return linked.push(d);
        });
        for (var j = 0; j < marker.markers.length; j++) {
            var subMarker = marker.markers[j];
            if (indexOf(linked, subMarker.doc) == -1) {
                subMarker.parent = null;
                marker.markers.splice(j--, 1);
            }
        }
    };

    for (var i = 0; i < markers.length; i++) loop(i);
}

var nextDocId = 0;
var Doc = function (text, mode, firstLine, lineSep, direction) {
    if (!(this instanceof Doc)) {
        return new Doc(text, mode, firstLine, lineSep, direction)
    }
    if (firstLine == null) {
        firstLine = 0;
    }

    BranchChunk.call(this, [new LeafChunk([new Line("", null)])]);
    this.first = firstLine;
    this.scrollTop = this.scrollLeft = 0;
    this.cantEdit = false;
    this.cleanGeneration = 1;
    this.modeFrontier = this.highlightFrontier = firstLine;
    var start = Pos(firstLine, 0);
    this.sel = simpleSelection(start);
    this.history = new History(null);
    this.id = ++nextDocId;
    this.modeOption = mode;
    this.lineSep = lineSep;
    this.direction = (direction == "rtl") ? "rtl" : "ltr";
    this.extend = false;

    if (typeof text == "string") {
        text = this.splitLines(text);
    }
    updateDoc(this, {from: start, to: start, text: text});
    setSelection(this, simpleSelection(start), sel_dontScroll);
};

Doc.prototype = createObj(BranchChunk.prototype, {
    constructor: Doc,
    // Iterate over the document. Supports two forms -- with only one
    // argument, it calls that for each line in the document. With
    // three, it iterates over the range given by the first two (with
    // the second being non-inclusive).
    iter: function (from, to, op) {
        if (op) {
            this.iterN(from - this.first, to - from, op);
        } else {
            this.iterN(this.first, this.first + this.size, from);
        }
    },

    // Non-public interface for adding and removing lines.
    insert: function (at, lines) {
        var height = 0;
        for (var i = 0; i < lines.length; ++i) {
            height += lines[i].height;
        }
        this.insertInner(at - this.first, lines, height);
    },
    remove: function (at, n) {
        this.removeInner(at - this.first, n);
    },
    getValue: function (lineSep) {
        var lines = getLines(this, this.first, this.first + this.size);
        if (lineSep === false) {
            return lines
        }
        return lines.join(lineSep || this.lineSeparator())
    },
    setValue: docMethodOp(function (code) {
        var top = Pos(this.first, 0), last = this.first + this.size - 1;
        makeChange(this, {
            from: top, to: Pos(last, getLine(this, last).text.length),
            text: this.splitLines(code), origin: "setValue", full: true
        }, true);
        if (this.cm) {
            scrollToCoords(this.cm, 0, 0);
        }
        setSelection(this, simpleSelection(top), sel_dontScroll);
    }),
    replaceRange: function (code, from, to, origin) {
        from = clipPos(this, from);
        to = to ? clipPos(this, to) : from;
        replaceRange(this, code, from, to, origin);
    },
    getRange: function (from, to, lineSep) {
        var lines = getBetween(this, clipPos(this, from), clipPos(this, to));
        if (lineSep === false) {
            return lines
        }
        return lines.join(lineSep || this.lineSeparator())
    },

    getLine: function (line) {
        var l = this.getLineHandle(line);
        return l && l.text
    },

    getLineHandle: function (line) {
        if (isLine(this, line)) {
            return getLine(this, line)
        }
    },
    getLineNumber: function (line) {
        return lineNo(line)
    },

    getLineHandleVisualStart: function (line) {
        if (typeof line == "number") {
            line = getLine(this, line);
        }
        return visualLine(line)
    },

    lineCount: function () {
        return this.size
    },
    firstLine: function () {
        return this.first
    },
    lastLine: function () {
        return this.first + this.size - 1
    },

    clipPos: function (pos) {
        return clipPos(this, pos)
    },

    getCursor: function (start) {
        var range$$1 = this.sel.primary(), pos;
        if (start == null || start == "head") {
            pos = range$$1.head;
        } else if (start == "anchor") {
            pos = range$$1.anchor;
        } else if (start == "end" || start == "to" || start === false) {
            pos = range$$1.to();
        } else {
            pos = range$$1.from();
        }
        return pos
    },
    listSelections: function () {
        return this.sel.ranges
    },
    somethingSelected: function () {
        return this.sel.somethingSelected()
    },

    setCursor: docMethodOp(function (line, ch, options) {
        setSimpleSelection(this, clipPos(this, typeof line == "number" ? Pos(line, ch || 0) : line), null, options);
    }),
    setSelection: docMethodOp(function (anchor, head, options) {
        setSimpleSelection(this, clipPos(this, anchor), clipPos(this, head || anchor), options);
    }),
    extendSelection: docMethodOp(function (head, other, options) {
        extendSelection(this, clipPos(this, head), other && clipPos(this, other), options);
    }),
    extendSelections: docMethodOp(function (heads, options) {
        extendSelections(this, clipPosArray(this, heads), options);
    }),
    extendSelectionsBy: docMethodOp(function (f, options) {
        var heads = map(this.sel.ranges, f);
        extendSelections(this, clipPosArray(this, heads), options);
    }),
    setSelections: docMethodOp(function (ranges, primary, options) {
        var this$1 = this;

        if (!ranges.length) {
            return
        }
        var out = [];
        for (var i = 0; i < ranges.length; i++) {
            out[i] = new Range(clipPos(this$1, ranges[i].anchor),
                clipPos(this$1, ranges[i].head));
        }
        if (primary == null) {
            primary = Math.min(ranges.length - 1, this.sel.primIndex);
        }
        setSelection(this, normalizeSelection(this.cm, out, primary), options);
    }),
    addSelection: docMethodOp(function (anchor, head, options) {
        var ranges = this.sel.ranges.slice(0);
        ranges.push(new Range(clipPos(this, anchor), clipPos(this, head || anchor)));
        setSelection(this, normalizeSelection(this.cm, ranges, ranges.length - 1), options);
    }),

    getSelection: function (lineSep) {
        var this$1 = this;

        var ranges = this.sel.ranges, lines;
        for (var i = 0; i < ranges.length; i++) {
            var sel = getBetween(this$1, ranges[i].from(), ranges[i].to());
            lines = lines ? lines.concat(sel) : sel;
        }
        if (lineSep === false) {
            return lines
        } else {
            return lines.join(lineSep || this.lineSeparator())
        }
    },
    getSelections: function (lineSep) {
        var this$1 = this;

        var parts = [], ranges = this.sel.ranges;
        for (var i = 0; i < ranges.length; i++) {
            var sel = getBetween(this$1, ranges[i].from(), ranges[i].to());
            if (lineSep !== false) {
                sel = sel.join(lineSep || this$1.lineSeparator());
            }
            parts[i] = sel;
        }
        return parts
    },
    replaceSelection: function (code, collapse, origin) {
        var dup = [];
        for (var i = 0; i < this.sel.ranges.length; i++) {
            dup[i] = code;
        }
        this.replaceSelections(dup, collapse, origin || "+input");
    },
    replaceSelections: docMethodOp(function (code, collapse, origin) {
        var this$1 = this;

        var changes = [], sel = this.sel;
        for (var i = 0; i < sel.ranges.length; i++) {
            var range$$1 = sel.ranges[i];
            changes[i] = {from: range$$1.from(), to: range$$1.to(), text: this$1.splitLines(code[i]), origin: origin};
        }
        var newSel = collapse && collapse != "end" && computeReplacedSel(this, changes, collapse);
        for (var i$1 = changes.length - 1; i$1 >= 0; i$1--) {
            makeChange(this$1, changes[i$1]);
        }
        if (newSel) {
            setSelectionReplaceHistory(this, newSel);
        } else if (this.cm) {
            ensureCursorVisible(this.cm);
        }
    }),
    undo: docMethodOp(function () {
        makeChangeFromHistory(this, "undo");
    }),
    redo: docMethodOp(function () {
        makeChangeFromHistory(this, "redo");
    }),
    undoSelection: docMethodOp(function () {
        makeChangeFromHistory(this, "undo", true);
    }),
    redoSelection: docMethodOp(function () {
        makeChangeFromHistory(this, "redo", true);
    }),

    setExtending: function (val) {
        this.extend = val;
    },
    getExtending: function () {
        return this.extend
    },

    historySize: function () {
        var hist = this.history, done = 0, undone = 0;
        for (var i = 0; i < hist.done.length; i++) {
            if (!hist.done[i].ranges) {
                ++done;
            }
        }
        for (var i$1 = 0; i$1 < hist.undone.length; i$1++) {
            if (!hist.undone[i$1].ranges) {
                ++undone;
            }
        }
        return {undo: done, redo: undone}
    },
    clearHistory: function () {
        this.history = new History(this.history.maxGeneration);
    },

    markClean: function () {
        this.cleanGeneration = this.changeGeneration(true);
    },
    changeGeneration: function (forceSplit) {
        if (forceSplit) {
            this.history.lastOp = this.history.lastSelOp = this.history.lastOrigin = null;
        }
        return this.history.generation
    },
    isClean: function (gen) {
        return this.history.generation == (gen || this.cleanGeneration)
    },

    getHistory: function () {
        return {
            done: copyHistoryArray(this.history.done),
            undone: copyHistoryArray(this.history.undone)
        }
    },
    setHistory: function (histData) {
        var hist = this.history = new History(this.history.maxGeneration);
        hist.done = copyHistoryArray(histData.done.slice(0), null, true);
        hist.undone = copyHistoryArray(histData.undone.slice(0), null, true);
    },

    setGutterMarker: docMethodOp(function (line, gutterID, value) {
        return changeLine(this, line, "gutter", function (line) {
            var markers = line.gutterMarkers || (line.gutterMarkers = {});
            markers[gutterID] = value;
            if (!value && isEmpty(markers)) {
                line.gutterMarkers = null;
            }
            return true
        })
    }),

    clearGutter: docMethodOp(function (gutterID) {
        var this$1 = this;

        this.iter(function (line) {
            if (line.gutterMarkers && line.gutterMarkers[gutterID]) {
                changeLine(this$1, line, "gutter", function () {
                    line.gutterMarkers[gutterID] = null;
                    if (isEmpty(line.gutterMarkers)) {
                        line.gutterMarkers = null;
                    }
                    return true
                });
            }
        });
    }),

    lineInfo: function (line) {
        var n;
        if (typeof line == "number") {
            if (!isLine(this, line)) {
                return null
            }
            n = line;
            line = getLine(this, line);
            if (!line) {
                return null
            }
        } else {
            n = lineNo(line);
            if (n == null) {
                return null
            }
        }
        return {
            line: n, handle: line, text: line.text, gutterMarkers: line.gutterMarkers,
            textClass: line.textClass, bgClass: line.bgClass, wrapClass: line.wrapClass,
            widgets: line.widgets
        }
    },

    addLineClass: docMethodOp(function (handle, where, cls) {
        return changeLine(this, handle, where == "gutter" ? "gutter" : "class", function (line) {
            var prop = where == "text" ? "textClass"
                : where == "background" ? "bgClass"
                    : where == "gutter" ? "gutterClass" : "wrapClass";
            if (!line[prop]) {
                line[prop] = cls;
            } else if (classTest(cls).test(line[prop])) {
                return false
            } else {
                line[prop] += " " + cls;
            }
            return true
        })
    }),
    removeLineClass: docMethodOp(function (handle, where, cls) {
        return changeLine(this, handle, where == "gutter" ? "gutter" : "class", function (line) {
            var prop = where == "text" ? "textClass"
                : where == "background" ? "bgClass"
                    : where == "gutter" ? "gutterClass" : "wrapClass";
            var cur = line[prop];
            if (!cur) {
                return false
            } else if (cls == null) {
                line[prop] = null;
            } else {
                var found = cur.match(classTest(cls));
                if (!found) {
                    return false
                }
                var end = found.index + found[0].length;
                line[prop] = cur.slice(0, found.index) + (!found.index || end == cur.length ? "" : " ") + cur.slice(end) || null;
            }
            return true
        })
    }),

    addLineWidget: docMethodOp(function (handle, node, options) {
        return addLineWidget(this, handle, node, options)
    }),
    removeLineWidget: function (widget) {
        widget.clear();
    },

    markText: function (from, to, options) {
        return markText(this, clipPos(this, from), clipPos(this, to), options, options && options.type || "range")
    },
    setBookmark: function (pos, options) {
        var realOpts = {
            replacedWith: options && (options.nodeType == null ? options.widget : options),
            insertLeft: options && options.insertLeft,
            clearWhenEmpty: false, shared: options && options.shared,
            handleMouseEvents: options && options.handleMouseEvents
        };
        pos = clipPos(this, pos);
        return markText(this, pos, pos, realOpts, "bookmark")
    },
    findMarksAt: function (pos) {
        pos = clipPos(this, pos);
        var markers = [], spans = getLine(this, pos.line).markedSpans;
        if (spans) {
            for (var i = 0; i < spans.length; ++i) {
                var span = spans[i];
                if ((span.from == null || span.from <= pos.ch) &&
                    (span.to == null || span.to >= pos.ch)) {
                    markers.push(span.marker.parent || span.marker);
                }
            }
        }
        return markers
    },
    findMarks: function (from, to, filter) {
        from = clipPos(this, from);
        to = clipPos(this, to);
        var found = [], lineNo$$1 = from.line;
        this.iter(from.line, to.line + 1, function (line) {
            var spans = line.markedSpans;
            if (spans) {
                for (var i = 0; i < spans.length; i++) {
                    var span = spans[i];
                    if (!(span.to != null && lineNo$$1 == from.line && from.ch >= span.to ||
                        span.from == null && lineNo$$1 != from.line ||
                        span.from != null && lineNo$$1 == to.line && span.from >= to.ch) &&
                        (!filter || filter(span.marker))) {
                        found.push(span.marker.parent || span.marker);
                    }
                }
            }
            ++lineNo$$1;
        });
        return found
    },
    getAllMarks: function () {
        var markers = [];
        this.iter(function (line) {
            var sps = line.markedSpans;
            if (sps) {
                for (var i = 0; i < sps.length; ++i) {
                    if (sps[i].from != null) {
                        markers.push(sps[i].marker);
                    }
                }
            }
        });
        return markers
    },

    posFromIndex: function (off) {
        var ch, lineNo$$1 = this.first, sepSize = this.lineSeparator().length;
        this.iter(function (line) {
            var sz = line.text.length + sepSize;
            if (sz > off) {
                ch = off;
                return true
            }
            off -= sz;
            ++lineNo$$1;
        });
        return clipPos(this, Pos(lineNo$$1, ch))
    },
    indexFromPos: function (coords) {
        coords = clipPos(this, coords);
        var index = coords.ch;
        if (coords.line < this.first || coords.ch < 0) {
            return 0
        }
        var sepSize = this.lineSeparator().length;
        this.iter(this.first, coords.line, function (line) { // iter aborts when callback returns a truthy value
            index += line.text.length + sepSize;
        });
        return index
    },

    copy: function (copyHistory) {
        var doc = new Doc(getLines(this, this.first, this.first + this.size),
            this.modeOption, this.first, this.lineSep, this.direction);
        doc.scrollTop = this.scrollTop;
        doc.scrollLeft = this.scrollLeft;
        doc.sel = this.sel;
        doc.extend = false;
        if (copyHistory) {
            doc.history.undoDepth = this.history.undoDepth;
            doc.setHistory(this.getHistory());
        }
        return doc
    },

    linkedDoc: function (options) {
        if (!options) {
            options = {};
        }
        var from = this.first, to = this.first + this.size;
        if (options.from != null && options.from > from) {
            from = options.from;
        }
        if (options.to != null && options.to < to) {
            to = options.to;
        }
        var copy = new Doc(getLines(this, from, to), options.mode || this.modeOption, from, this.lineSep, this.direction);
        if (options.sharedHist) {
            copy.history = this.history
            ;
        }
        (this.linked || (this.linked = [])).push({doc: copy, sharedHist: options.sharedHist});
        copy.linked = [{doc: this, isParent: true, sharedHist: options.sharedHist}];
        copySharedMarkers(copy, findSharedMarkers(this));
        return copy
    },
    unlinkDoc: function (other) {
        var this$1 = this;

        if (other instanceof CodeMirror) {
            other = other.doc;
        }
        if (this.linked) {
            for (var i = 0; i < this.linked.length; ++i) {
                var link = this$1.linked[i];
                if (link.doc != other) {
                    continue
                }
                this$1.linked.splice(i, 1);
                other.unlinkDoc(this$1);
                detachSharedMarkers(findSharedMarkers(this$1));
                break
            }
        }
        // If the histories were shared, split them again
        if (other.history == this.history) {
            var splitIds = [other.id];
            linkedDocs(other, function (doc) {
                return splitIds.push(doc.id);
            }, true);
            other.history = new History(null);
            other.history.done = copyHistoryArray(this.history.done, splitIds);
            other.history.undone = copyHistoryArray(this.history.undone, splitIds);
        }
    },
    iterLinkedDocs: function (f) {
        linkedDocs(this, f);
    },

    getMode: function () {
        return this.mode
    },
    getEditor: function () {
        return this.cm
    },

    splitLines: function (str) {
        if (this.lineSep) {
            return str.split(this.lineSep)
        }
        return splitLinesAuto(str)
    },
    lineSeparator: function () {
        return this.lineSep || "\n"
    },

    setDirection: docMethodOp(function (dir) {
        if (dir != "rtl") {
            dir = "ltr";
        }
        if (dir == this.direction) {
            return
        }
        this.direction = dir;
        this.iter(function (line) {
            return line.order = null;
        });
        if (this.cm) {
            directionChanged(this.cm);
        }
    })
});

// Public alias.
Doc.prototype.eachLine = Doc.prototype.iter;

// Kludge to work around strange IE behavior where it'll sometimes
// re-fire a series of drag-related events right after the drop (#1551)
var lastDrop = 0;

function onDrop(e) {
    var cm = this;
    clearDragCursor(cm);
    if (signalDOMEvent(cm, e) || eventInWidget(cm.display, e)) {
        return
    }
    e_preventDefault(e);
    if (ie) {
        lastDrop = +new Date;
    }
    var pos = posFromMouse(cm, e, true), files = e.dataTransfer.files;
    if (!pos || cm.isReadOnly()) {
        return
    }
    // Might be a file drop, in which case we simply extract the text
    // and insert it.
    if (files && files.length && window.FileReader && window.File) {
        var n = files.length, text = Array(n), read = 0;
        var loadFile = function (file, i) {
            if (cm.options.allowDropFileTypes &&
                indexOf(cm.options.allowDropFileTypes, file.type) == -1) {
                return
            }

            var reader = new FileReader;
            reader.onload = operation(cm, function () {
                var content = reader.result;
                if (/[\x00-\x08\x0e-\x1f]{2}/.test(content)) {
                    content = "";
                }
                text[i] = content;
                if (++read == n) {
                    pos = clipPos(cm.doc, pos);
                    var change = {
                        from: pos, to: pos,
                        text: cm.doc.splitLines(text.join(cm.doc.lineSeparator())),
                        origin: "paste"
                    };
                    makeChange(cm.doc, change);
                    setSelectionReplaceHistory(cm.doc, simpleSelection(pos, changeEnd(change)));
                }
            });
            reader.readAsText(file);
        };
        for (var i = 0; i < n; ++i) {
            loadFile(files[i], i);
        }
    } else { // Normal drop
        // Don't do a replace if the drop happened inside of the selected text.
        if (cm.state.draggingText && cm.doc.sel.contains(pos) > -1) {
            cm.state.draggingText(e);
            // Ensure the src is re-focused
            setTimeout(function () {
                return cm.display.input.focus();
            }, 20);
            return
        }
        try {
            var text$1 = e.dataTransfer.getData("Text");
            if (text$1) {
                var selected;
                if (cm.state.draggingText && !cm.state.draggingText.copy) {
                    selected = cm.listSelections();
                }
                setSelectionNoUndo(cm.doc, simpleSelection(pos, pos));
                if (selected) {
                    for (var i$1 = 0; i$1 < selected.length; ++i$1) {
                        replaceRange(cm.doc, "", selected[i$1].anchor, selected[i$1].head, "drag");
                    }
                }
                cm.replaceSelection(text$1, "around", "paste");
                cm.display.input.focus();
            }
        } catch (e) {
        }
    }
}

function onDragStart(cm, e) {
    if (ie && (!cm.state.draggingText || +new Date - lastDrop < 100)) {
        e_stop(e);
        return
    }
    if (signalDOMEvent(cm, e) || eventInWidget(cm.display, e)) {
        return
    }

    e.dataTransfer.setData("Text", cm.getSelection());
    e.dataTransfer.effectAllowed = "copyMove";

    // Use dummy image instead of default browsers image.
    // Recent Safari (~6.0.2) have a tendency to segfault when this happens, so we don't do it there.
    if (e.dataTransfer.setDragImage && !safari) {
        var img = elt("img", null, null, "position: fixed; left: 0; top: 0;");
        img.src = "";
        if (presto) {
            img.width = img.height = 1;
            cm.display.wrapper.appendChild(img);
            // Force a relayout, or Opera won't use our image for some obscure reason
            img._top = img.offsetTop;
        }
        e.dataTransfer.setDragImage(img, 0, 0);
        if (presto) {
            img.parentNode.removeChild(img);
        }
    }
}

function onDragOver(cm, e) {
    var pos = posFromMouse(cm, e);
    if (!pos) {
        return
    }
    var frag = document.createDocumentFragment();
    drawSelectionCursor(cm, pos, frag);
    if (!cm.display.dragCursor) {
        cm.display.dragCursor = elt("div", null, "CodeMirror-cursors CodeMirror-dragcursors");
        cm.display.lineSpace.insertBefore(cm.display.dragCursor, cm.display.cursorDiv);
    }
    removeChildrenAndAdd(cm.display.dragCursor, frag);
}

function clearDragCursor(cm) {
    if (cm.display.dragCursor) {
        cm.display.lineSpace.removeChild(cm.display.dragCursor);
        cm.display.dragCursor = null;
    }
}

// These must be handled carefully, because naively registering a
// handler for each src will cause the editors to never be
// garbage collected.

function forEachCodeMirror(f) {
    if (!document.getElementsByClassName) {
        return
    }
    var byClass = document.getElementsByClassName("CodeMirror"), editors = [];
    for (var i = 0; i < byClass.length; i++) {
        var cm = byClass[i].CodeMirror;
        if (cm) {
            editors.push(cm);
        }
    }
    if (editors.length) {
        editors[0].operation(function () {
            for (var i = 0; i < editors.length; i++) {
                f(editors[i]);
            }
        });
    }
}

var globalsRegistered = false;

function ensureGlobalHandlers() {
    if (globalsRegistered) {
        return
    }
    registerGlobalHandlers();
    globalsRegistered = true;
}

function registerGlobalHandlers() {
    // When the window resizes, we need to refresh active editors.
    var resizeTimer;
    on(window, "resize", function () {
        if (resizeTimer == null) {
            resizeTimer = setTimeout(function () {
                resizeTimer = null;
                forEachCodeMirror(onResize);
            }, 100);
        }
    });
    // When the window loses focus, we want to show the src as blurred
    on(window, "blur", function () {
        return forEachCodeMirror(onBlur);
    });
}

// Called when the window resizes
function onResize(cm) {
    var d = cm.display;
    // Might be a text scaling operation, clear size caches.
    d.cachedCharWidth = d.cachedTextHeight = d.cachedPaddingH = null;
    d.scrollbarsClipped = false;
    cm.setSize();
}

var keyNames = {
    3: "Pause", 8: "Backspace", 9: "Tab", 13: "Enter", 16: "Shift", 17: "Ctrl", 18: "Alt",
    19: "Pause", 20: "CapsLock", 27: "Esc", 32: "Space", 33: "PageUp", 34: "PageDown", 35: "End",
    36: "Home", 37: "Left", 38: "Up", 39: "Right", 40: "Down", 44: "PrintScrn", 45: "Insert",
    46: "Delete", 59: ";", 61: "=", 91: "Mod", 92: "Mod", 93: "Mod",
    106: "*", 107: "=", 109: "-", 110: ".", 111: "/", 145: "ScrollLock",
    173: "-", 186: ";", 187: "=", 188: ",", 189: "-", 190: ".", 191: "/", 192: "`", 219: "[", 220: "\\",
    221: "]", 222: "'", 63232: "Up", 63233: "Down", 63234: "Left", 63235: "Right", 63272: "Delete",
    63273: "Home", 63275: "End", 63276: "PageUp", 63277: "PageDown", 63302: "Insert"
};

// Number keys
for (var i = 0; i < 10; i++) {
    keyNames[i + 48] = keyNames[i + 96] = String(i);
}
// Alphabetic keys
for (var i$1 = 65; i$1 <= 90; i$1++) {
    keyNames[i$1] = String.fromCharCode(i$1);
}
// Function keys
for (var i$2 = 1; i$2 <= 12; i$2++) {
    keyNames[i$2 + 111] = keyNames[i$2 + 63235] = "F" + i$2;
}

var keyMap = {};

keyMap.basic = {
    "Left": "goCharLeft", "Right": "goCharRight", "Up": "goLineUp", "Down": "goLineDown",
    "End": "goLineEnd", "Home": "goLineStartSmart", "PageUp": "goPageUp", "PageDown": "goPageDown",
    "Delete": "delCharAfter", "Backspace": "delCharBefore", "Shift-Backspace": "delCharBefore",
    "Tab": "defaultTab", "Shift-Tab": "indentAuto",
    "Enter": "newlineAndIndent", "Insert": "toggleOverwrite",
    "Esc": "singleSelection"
};
// Note that the save and find-related commands aren't defined by
// default. User code or addons can define them. Unknown commands
// are simply ignored.
keyMap.pcDefault = {
    "Ctrl-A": "selectAll", "Ctrl-D": "deleteLine", "Ctrl-Z": "undo", "Shift-Ctrl-Z": "redo", "Ctrl-Y": "redo",
    "Ctrl-Home": "goDocStart", "Ctrl-End": "goDocEnd", "Ctrl-Up": "goLineUp", "Ctrl-Down": "goLineDown",
    "Ctrl-Left": "goGroupLeft", "Ctrl-Right": "goGroupRight", "Alt-Left": "goLineStart", "Alt-Right": "goLineEnd",
    "Ctrl-Backspace": "delGroupBefore", "Ctrl-Delete": "delGroupAfter", "Ctrl-S": "save", "Ctrl-F": "find",
    "Ctrl-G": "findNext", "Shift-Ctrl-G": "findPrev", "Shift-Ctrl-F": "replace", "Shift-Ctrl-R": "replaceAll",
    "Ctrl-[": "indentLess", "Ctrl-]": "indentMore",
    "Ctrl-U": "undoSelection", "Shift-Ctrl-U": "redoSelection", "Alt-U": "redoSelection",
    "fallthrough": "basic"
};
// Very basic readline/emacs-style bindings, which are standard on Mac.
keyMap.emacsy = {
    "Ctrl-F": "goCharRight", "Ctrl-B": "goCharLeft", "Ctrl-P": "goLineUp", "Ctrl-N": "goLineDown",
    "Alt-F": "goWordRight", "Alt-B": "goWordLeft", "Ctrl-A": "goLineStart", "Ctrl-E": "goLineEnd",
    "Ctrl-V": "goPageDown", "Shift-Ctrl-V": "goPageUp", "Ctrl-D": "delCharAfter", "Ctrl-H": "delCharBefore",
    "Alt-D": "delWordAfter", "Alt-Backspace": "delWordBefore", "Ctrl-K": "killLine", "Ctrl-T": "transposeChars",
    "Ctrl-O": "openLine"
};
keyMap.macDefault = {
    "Cmd-A": "selectAll",
    "Cmd-D": "deleteLine",
    "Cmd-Z": "undo",
    "Shift-Cmd-Z": "redo",
    "Cmd-Y": "redo",
    "Cmd-Home": "goDocStart",
    "Cmd-Up": "goDocStart",
    "Cmd-End": "goDocEnd",
    "Cmd-Down": "goDocEnd",
    "Alt-Left": "goGroupLeft",
    "Alt-Right": "goGroupRight",
    "Cmd-Left": "goLineLeft",
    "Cmd-Right": "goLineRight",
    "Alt-Backspace": "delGroupBefore",
    "Ctrl-Alt-Backspace": "delGroupAfter",
    "Alt-Delete": "delGroupAfter",
    "Cmd-S": "save",
    "Cmd-F": "find",
    "Cmd-G": "findNext",
    "Shift-Cmd-G": "findPrev",
    "Cmd-Alt-F": "replace",
    "Shift-Cmd-Alt-F": "replaceAll",
    "Cmd-[": "indentLess",
    "Cmd-]": "indentMore",
    "Cmd-Backspace": "delWrappedLineLeft",
    "Cmd-Delete": "delWrappedLineRight",
    "Cmd-U": "undoSelection",
    "Shift-Cmd-U": "redoSelection",
    "Ctrl-Up": "goDocStart",
    "Ctrl-Down": "goDocEnd",
    "fallthrough": ["basic", "emacsy"]
};
keyMap["default"] = mac ? keyMap.macDefault : keyMap.pcDefault;

// KEYMAP DISPATCH

function normalizeKeyName(name) {
    var parts = name.split(/-(?!$)/);
    name = parts[parts.length - 1];
    var alt, ctrl, shift, cmd;
    for (var i = 0; i < parts.length - 1; i++) {
        var mod = parts[i];
        if (/^(cmd|meta|m)$/i.test(mod)) {
            cmd = true;
        } else if (/^a(lt)?$/i.test(mod)) {
            alt = true;
        } else if (/^(c|ctrl|control)$/i.test(mod)) {
            ctrl = true;
        } else if (/^s(hift)?$/i.test(mod)) {
            shift = true;
        } else {
            throw new Error("Unrecognized modifier name: " + mod)
        }
    }
    if (alt) {
        name = "Alt-" + name;
    }
    if (ctrl) {
        name = "Ctrl-" + name;
    }
    if (cmd) {
        name = "Cmd-" + name;
    }
    if (shift) {
        name = "Shift-" + name;
    }
    return name
}

// This is a kludge to keep keymaps mostly working as raw objects
// (backwards compatibility) while at the same time support features
// like normalization and multi-stroke key bindings. It compiles a
// new normalized keymap, and then updates the old object to reflect
// this.
function normalizeKeyMap(keymap) {
    var copy = {};
    for (var keyname in keymap) {
        if (keymap.hasOwnProperty(keyname)) {
            var value = keymap[keyname];
            if (/^(name|fallthrough|(de|at)tach)$/.test(keyname)) {
                continue
            }
            if (value == "...") {
                delete keymap[keyname];
                continue
            }

            var keys = map(keyname.split(" "), normalizeKeyName);
            for (var i = 0; i < keys.length; i++) {
                var val = (void 0), name = (void 0);
                if (i == keys.length - 1) {
                    name = keys.join(" ");
                    val = value;
                } else {
                    name = keys.slice(0, i + 1).join(" ");
                    val = "...";
                }
                var prev = copy[name];
                if (!prev) {
                    copy[name] = val;
                } else if (prev != val) {
                    throw new Error("Inconsistent bindings for " + name)
                }
            }
            delete keymap[keyname];
        }
    }
    for (var prop in copy) {
        keymap[prop] = copy[prop];
    }
    return keymap
}

function lookupKey(key, map$$1, handle, context) {
    map$$1 = getKeyMap(map$$1);
    var found = map$$1.call ? map$$1.call(key, context) : map$$1[key];
    if (found === false) {
        return "nothing"
    }
    if (found === "...") {
        return "multi"
    }
    if (found != null && handle(found)) {
        return "handled"
    }

    if (map$$1.fallthrough) {
        if (Object.prototype.toString.call(map$$1.fallthrough) != "[object Array]") {
            return lookupKey(key, map$$1.fallthrough, handle, context)
        }
        for (var i = 0; i < map$$1.fallthrough.length; i++) {
            var result = lookupKey(key, map$$1.fallthrough[i], handle, context);
            if (result) {
                return result
            }
        }
    }
}

// Modifier key presses don't count as 'real' key presses for the
// purpose of keymap fallthrough.
function isModifierKey(value) {
    var name = typeof value == "string" ? value : keyNames[value.keyCode];
    return name == "Ctrl" || name == "Alt" || name == "Shift" || name == "Mod"
}

function addModifierNames(name, event, noShift) {
    var base = name;
    if (event.altKey && base != "Alt") {
        name = "Alt-" + name;
    }
    if ((flipCtrlCmd ? event.metaKey : event.ctrlKey) && base != "Ctrl") {
        name = "Ctrl-" + name;
    }
    if ((flipCtrlCmd ? event.ctrlKey : event.metaKey) && base != "Cmd") {
        name = "Cmd-" + name;
    }
    if (!noShift && event.shiftKey && base != "Shift") {
        name = "Shift-" + name;
    }
    return name
}

// Look up the name of a key as indicated by an event object.
function keyName(event, noShift) {
    if (presto && event.keyCode == 34 && event["char"]) {
        return false
    }
    var name = keyNames[event.keyCode];
    if (name == null || event.altGraphKey) {
        return false
    }
    // Ctrl-ScrollLock has keyCode 3, same as Ctrl-Pause,
    // so we'll use event.code when available (Chrome 48+, FF 38+, Safari 10.1+)
    if (event.keyCode == 3 && event.code) {
        name = event.code;
    }
    return addModifierNames(name, event, noShift)
}

function getKeyMap(val) {
    return typeof val == "string" ? keyMap[val] : val
}

// Helper for deleting text near the selection(s), used to implement
// backspace, delete, and similar functionality.
function deleteNearSelection(cm, compute) {
    var ranges = cm.doc.sel.ranges, kill = [];
    // Build up a set of ranges to kill first, merging overlapping
    // ranges.
    for (var i = 0; i < ranges.length; i++) {
        var toKill = compute(ranges[i]);
        while (kill.length && cmp(toKill.from, lst(kill).to) <= 0) {
            var replaced = kill.pop();
            if (cmp(replaced.from, toKill.from) < 0) {
                toKill.from = replaced.from;
                break
            }
        }
        kill.push(toKill);
    }
    // Next, remove those actual ranges.
    runInOp(cm, function () {
        for (var i = kill.length - 1; i >= 0; i--) {
            replaceRange(cm.doc, "", kill[i].from, kill[i].to, "+delete");
        }
        ensureCursorVisible(cm);
    });
}

function moveCharLogically(line, ch, dir) {
    var target = skipExtendingChars(line.text, ch + dir, dir);
    return target < 0 || target > line.text.length ? null : target
}

function moveLogically(line, start, dir) {
    var ch = moveCharLogically(line, start.ch, dir);
    return ch == null ? null : new Pos(start.line, ch, dir < 0 ? "after" : "before")
}

function endOfLine(visually, cm, lineObj, lineNo, dir) {
    if (visually) {
        var order = getOrder(lineObj, cm.doc.direction);
        if (order) {
            var part = dir < 0 ? lst(order) : order[0];
            var moveInStorageOrder = (dir < 0) == (part.level == 1);
            var sticky = moveInStorageOrder ? "after" : "before";
            var ch;
            if (part.level > 0 || cm.doc.direction == "rtl") {
                var prep = prepareMeasureForLine(cm, lineObj);
                ch = dir < 0 ? lineObj.text.length - 1 : 0;
                var targetTop = measureCharPrepared(cm, prep, ch).top;
                ch = findFirst(function (ch) {
                    return measureCharPrepared(cm, prep, ch).top == targetTop;
                }, (dir < 0) == (part.level == 1) ? part.from : part.to - 1, ch);
                if (sticky == "before") {
                    ch = moveCharLogically(lineObj, ch, 1);
                }
            } else {
                ch = dir < 0 ? part.to : part.from;
            }
            return new Pos(lineNo, ch, sticky)
        }
    }
    return new Pos(lineNo, dir < 0 ? lineObj.text.length : 0, dir < 0 ? "before" : "after")
}

function moveVisually(cm, line, start, dir) {
    var bidi = getOrder(line, cm.doc.direction);
    if (!bidi) {
        return moveLogically(line, start, dir)
    }
    if (start.ch >= line.text.length) {
        start.ch = line.text.length;
        start.sticky = "before";
    } else if (start.ch <= 0) {
        start.ch = 0;
        start.sticky = "after";
    }
    var partPos = getBidiPartAt(bidi, start.ch, start.sticky), part = bidi[partPos];
    if (cm.doc.direction == "ltr" && part.level % 2 == 0 && (dir > 0 ? part.to > start.ch : part.from < start.ch)) {
        // Case 1: We move within an ltr part in an ltr src. Even with wrapped lines,
        // nothing interesting happens.
        return moveLogically(line, start, dir)
    }

    var mv = function (pos, dir) {
        return moveCharLogically(line, pos instanceof Pos ? pos.ch : pos, dir);
    };
    var prep;
    var getWrappedLineExtent = function (ch) {
        if (!cm.options.lineWrapping) {
            return {begin: 0, end: line.text.length}
        }
        prep = prep || prepareMeasureForLine(cm, line);
        return wrappedLineExtentChar(cm, line, prep, ch)
    };
    var wrappedLineExtent = getWrappedLineExtent(start.sticky == "before" ? mv(start, -1) : start.ch);

    if (cm.doc.direction == "rtl" || part.level == 1) {
        var moveInStorageOrder = (part.level == 1) == (dir < 0);
        var ch = mv(start, moveInStorageOrder ? 1 : -1);
        if (ch != null && (!moveInStorageOrder ? ch >= part.from && ch >= wrappedLineExtent.begin : ch <= part.to && ch <= wrappedLineExtent.end)) {
            // Case 2: We move within an rtl part or in an rtl src on the same visual line
            var sticky = moveInStorageOrder ? "before" : "after";
            return new Pos(start.line, ch, sticky)
        }
    }

    // Case 3: Could not move within this bidi part in this visual line, so leave
    // the current bidi part

    var searchInVisualLine = function (partPos, dir, wrappedLineExtent) {
        var getRes = function (ch, moveInStorageOrder) {
            return moveInStorageOrder
                ? new Pos(start.line, mv(ch, 1), "before")
                : new Pos(start.line, ch, "after");
        };

        for (; partPos >= 0 && partPos < bidi.length; partPos += dir) {
            var part = bidi[partPos];
            var moveInStorageOrder = (dir > 0) == (part.level != 1);
            var ch = moveInStorageOrder ? wrappedLineExtent.begin : mv(wrappedLineExtent.end, -1);
            if (part.from <= ch && ch < part.to) {
                return getRes(ch, moveInStorageOrder)
            }
            ch = moveInStorageOrder ? part.from : mv(part.to, -1);
            if (wrappedLineExtent.begin <= ch && ch < wrappedLineExtent.end) {
                return getRes(ch, moveInStorageOrder)
            }
        }
    };

    // Case 3a: Look for other bidi parts on the same visual line
    var res = searchInVisualLine(partPos + dir, dir, wrappedLineExtent);
    if (res) {
        return res
    }

    // Case 3b: Look for other bidi parts on the next visual line
    var nextCh = dir > 0 ? wrappedLineExtent.end : mv(wrappedLineExtent.begin, -1);
    if (nextCh != null && !(dir > 0 && nextCh == line.text.length)) {
        res = searchInVisualLine(dir > 0 ? 0 : bidi.length - 1, dir, getWrappedLineExtent(nextCh));
        if (res) {
            return res
        }
    }

    // Case 4: Nowhere to move
    return null
}

// Commands are parameter-less actions that can be performed on an
// src, mostly used for keybindings.
var commands = {
    selectAll: selectAll,
    singleSelection: function (cm) {
        return cm.setSelection(cm.getCursor("anchor"), cm.getCursor("head"), sel_dontScroll);
    },
    killLine: function (cm) {
        return deleteNearSelection(cm, function (range) {
            if (range.empty()) {
                var len = getLine(cm.doc, range.head.line).text.length;
                if (range.head.ch == len && range.head.line < cm.lastLine()) {
                    return {from: range.head, to: Pos(range.head.line + 1, 0)}
                } else {
                    return {from: range.head, to: Pos(range.head.line, len)}
                }
            } else {
                return {from: range.from(), to: range.to()}
            }
        });
    },
    deleteLine: function (cm) {
        return deleteNearSelection(cm, function (range) {
            return ({
                from: Pos(range.from().line, 0),
                to: clipPos(cm.doc, Pos(range.to().line + 1, 0))
            });
        });
    },
    delLineLeft: function (cm) {
        return deleteNearSelection(cm, function (range) {
            return ({
                from: Pos(range.from().line, 0), to: range.from()
            });
        });
    },
    delWrappedLineLeft: function (cm) {
        return deleteNearSelection(cm, function (range) {
            var top = cm.charCoords(range.head, "div").top + 5;
            var leftPos = cm.coordsChar({left: 0, top: top}, "div");
            return {from: leftPos, to: range.from()}
        });
    },
    delWrappedLineRight: function (cm) {
        return deleteNearSelection(cm, function (range) {
            var top = cm.charCoords(range.head, "div").top + 5;
            var rightPos = cm.coordsChar({left: cm.display.lineDiv.offsetWidth + 100, top: top}, "div");
            return {from: range.from(), to: rightPos}
        });
    },
    undo: function (cm) {
        return cm.undo();
    },
    redo: function (cm) {
        return cm.redo();
    },
    undoSelection: function (cm) {
        return cm.undoSelection();
    },
    redoSelection: function (cm) {
        return cm.redoSelection();
    },
    goDocStart: function (cm) {
        return cm.extendSelection(Pos(cm.firstLine(), 0));
    },
    goDocEnd: function (cm) {
        return cm.extendSelection(Pos(cm.lastLine()));
    },
    goLineStart: function (cm) {
        return cm.extendSelectionsBy(function (range) {
                return lineStart(cm, range.head.line);
            },
            {origin: "+move", bias: 1}
        );
    },
    goLineStartSmart: function (cm) {
        return cm.extendSelectionsBy(function (range) {
                return lineStartSmart(cm, range.head);
            },
            {origin: "+move", bias: 1}
        );
    },
    goLineEnd: function (cm) {
        return cm.extendSelectionsBy(function (range) {
                return lineEnd(cm, range.head.line);
            },
            {origin: "+move", bias: -1}
        );
    },
    goLineRight: function (cm) {
        return cm.extendSelectionsBy(function (range) {
            var top = cm.cursorCoords(range.head, "div").top + 5;
            return cm.coordsChar({left: cm.display.lineDiv.offsetWidth + 100, top: top}, "div")
        }, sel_move);
    },
    goLineLeft: function (cm) {
        return cm.extendSelectionsBy(function (range) {
            var top = cm.cursorCoords(range.head, "div").top + 5;
            return cm.coordsChar({left: 0, top: top}, "div")
        }, sel_move);
    },
    goLineLeftSmart: function (cm) {
        return cm.extendSelectionsBy(function (range) {
            var top = cm.cursorCoords(range.head, "div").top + 5;
            var pos = cm.coordsChar({left: 0, top: top}, "div");
            if (pos.ch < cm.getLine(pos.line).search(/\S/)) {
                return lineStartSmart(cm, range.head)
            }
            return pos
        }, sel_move);
    },
    goLineUp: function (cm) {
        return cm.moveV(-1, "line");
    },
    goLineDown: function (cm) {
        return cm.moveV(1, "line");
    },
    goPageUp: function (cm) {
        return cm.moveV(-1, "page");
    },
    goPageDown: function (cm) {
        return cm.moveV(1, "page");
    },
    goCharLeft: function (cm) {
        return cm.moveH(-1, "char");
    },
    goCharRight: function (cm) {
        return cm.moveH(1, "char");
    },
    goColumnLeft: function (cm) {
        return cm.moveH(-1, "column");
    },
    goColumnRight: function (cm) {
        return cm.moveH(1, "column");
    },
    goWordLeft: function (cm) {
        return cm.moveH(-1, "word");
    },
    goGroupRight: function (cm) {
        return cm.moveH(1, "group");
    },
    goGroupLeft: function (cm) {
        return cm.moveH(-1, "group");
    },
    goWordRight: function (cm) {
        return cm.moveH(1, "word");
    },
    delCharBefore: function (cm) {
        return cm.deleteH(-1, "char");
    },
    delCharAfter: function (cm) {
        return cm.deleteH(1, "char");
    },
    delWordBefore: function (cm) {
        return cm.deleteH(-1, "word");
    },
    delWordAfter: function (cm) {
        return cm.deleteH(1, "word");
    },
    delGroupBefore: function (cm) {
        return cm.deleteH(-1, "group");
    },
    delGroupAfter: function (cm) {
        return cm.deleteH(1, "group");
    },
    indentAuto: function (cm) {
        return cm.indentSelection("smart");
    },
    indentMore: function (cm) {
        return cm.indentSelection("add");
    },
    indentLess: function (cm) {
        return cm.indentSelection("subtract");
    },
    insertTab: function (cm) {
        return cm.replaceSelection("\t");
    },
    insertSoftTab: function (cm) {
        var spaces = [], ranges = cm.listSelections(), tabSize = cm.options.tabSize;
        for (var i = 0; i < ranges.length; i++) {
            var pos = ranges[i].from();
            var col = countColumn(cm.getLine(pos.line), pos.ch, tabSize);
            spaces.push(spaceStr(tabSize - col % tabSize));
        }
        cm.replaceSelections(spaces);
    },
    defaultTab: function (cm) {
        if (cm.somethingSelected()) {
            cm.indentSelection("add");
        } else {
            cm.execCommand("insertTab");
        }
    },
    // Swap the two chars left and right of each selection's head.
    // Move cursor behind the two swapped characters afterwards.
    //
    // Doesn't consider line feeds a character.
    // Doesn't scan more than one line above to find a character.
    // Doesn't do anything on an empty line.
    // Doesn't do anything with non-empty selections.
    transposeChars: function (cm) {
        return runInOp(cm, function () {
            var ranges = cm.listSelections(), newSel = [];
            for (var i = 0; i < ranges.length; i++) {
                if (!ranges[i].empty()) {
                    continue
                }
                var cur = ranges[i].head, line = getLine(cm.doc, cur.line).text;
                if (line) {
                    if (cur.ch == line.length) {
                        cur = new Pos(cur.line, cur.ch - 1);
                    }
                    if (cur.ch > 0) {
                        cur = new Pos(cur.line, cur.ch + 1);
                        cm.replaceRange(line.charAt(cur.ch - 1) + line.charAt(cur.ch - 2),
                            Pos(cur.line, cur.ch - 2), cur, "+transpose");
                    } else if (cur.line > cm.doc.first) {
                        var prev = getLine(cm.doc, cur.line - 1).text;
                        if (prev) {
                            cur = new Pos(cur.line, 1);
                            cm.replaceRange(line.charAt(0) + cm.doc.lineSeparator() +
                                prev.charAt(prev.length - 1),
                                Pos(cur.line - 1, prev.length - 1), cur, "+transpose");
                        }
                    }
                }
                newSel.push(new Range(cur, cur));
            }
            cm.setSelections(newSel);
        });
    },
    newlineAndIndent: function (cm) {
        return runInOp(cm, function () {
            var sels = cm.listSelections();
            for (var i = sels.length - 1; i >= 0; i--) {
                cm.replaceRange(cm.doc.lineSeparator(), sels[i].anchor, sels[i].head, "+input");
            }
            sels = cm.listSelections();
            for (var i$1 = 0; i$1 < sels.length; i$1++) {
                cm.indentLine(sels[i$1].from().line, null, true);
            }
            ensureCursorVisible(cm);
        });
    },
    openLine: function (cm) {
        return cm.replaceSelection("\n", "start");
    },
    toggleOverwrite: function (cm) {
        return cm.toggleOverwrite();
    }
};


function lineStart(cm, lineN) {
    var line = getLine(cm.doc, lineN);
    var visual = visualLine(line);
    if (visual != line) {
        lineN = lineNo(visual);
    }
    return endOfLine(true, cm, visual, lineN, 1)
}

function lineEnd(cm, lineN) {
    var line = getLine(cm.doc, lineN);
    var visual = visualLineEnd(line);
    if (visual != line) {
        lineN = lineNo(visual);
    }
    return endOfLine(true, cm, line, lineN, -1)
}

function lineStartSmart(cm, pos) {
    var start = lineStart(cm, pos.line);
    var line = getLine(cm.doc, start.line);
    var order = getOrder(line, cm.doc.direction);
    if (!order || order[0].level == 0) {
        var firstNonWS = Math.max(0, line.text.search(/\S/));
        var inWS = pos.line == start.line && pos.ch <= firstNonWS && pos.ch;
        return Pos(start.line, inWS ? 0 : firstNonWS, start.sticky)
    }
    return start
}

// Run a handler that was bound to a key.
function doHandleBinding(cm, bound, dropShift) {
    if (typeof bound == "string") {
        bound = commands[bound];
        if (!bound) {
            return false
        }
    }
    // Ensure previous input has been read, so that the handler sees a
    // consistent view of the document
    cm.display.input.ensurePolled();
    var prevShift = cm.display.shift, done = false;
    try {
        if (cm.isReadOnly()) {
            cm.state.suppressEdits = true;
        }
        if (dropShift) {
            cm.display.shift = false;
        }
        done = bound(cm) != Pass;
    } finally {
        cm.display.shift = prevShift;
        cm.state.suppressEdits = false;
    }
    return done
}

function lookupKeyForEditor(cm, name, handle) {
    for (var i = 0; i < cm.state.keyMaps.length; i++) {
        var result = lookupKey(name, cm.state.keyMaps[i], handle, cm);
        if (result) {
            return result
        }
    }
    return (cm.options.extraKeys && lookupKey(name, cm.options.extraKeys, handle, cm))
        || lookupKey(name, cm.options.keyMap, handle, cm)
}

// Note that, despite the name, this function is also used to check
// for bound mouse clicks.

var stopSeq = new Delayed;

function dispatchKey(cm, name, e, handle) {
    var seq = cm.state.keySeq;
    if (seq) {
        if (isModifierKey(name)) {
            return "handled"
        }
        if (/\'$/.test(name)) {
            cm.state.keySeq = null;
        } else {
            stopSeq.set(50, function () {
                if (cm.state.keySeq == seq) {
                    cm.state.keySeq = null;
                    cm.display.input.reset();
                }
            });
        }
        if (dispatchKeyInner(cm, seq + " " + name, e, handle)) {
            return true
        }
    }
    return dispatchKeyInner(cm, name, e, handle)
}

function dispatchKeyInner(cm, name, e, handle) {
    var result = lookupKeyForEditor(cm, name, handle);

    if (result == "multi") {
        cm.state.keySeq = name;
    }
    if (result == "handled") {
        signalLater(cm, "keyHandled", cm, name, e);
    }

    if (result == "handled" || result == "multi") {
        e_preventDefault(e);
        restartBlink(cm);
    }

    return !!result
}

// Handle a key from the keydown event.
function handleKeyBinding(cm, e) {
    var name = keyName(e, true);
    if (!name) {
        return false
    }

    if (e.shiftKey && !cm.state.keySeq) {
        // First try to resolve full name (including 'Shift-'). Failing
        // that, see if there is a cursor-motion command (starting with
        // 'go') bound to the keyname without 'Shift-'.
        return dispatchKey(cm, "Shift-" + name, e, function (b) {
                return doHandleBinding(cm, b, true);
            })
            || dispatchKey(cm, name, e, function (b) {
                if (typeof b == "string" ? /^go[A-Z]/.test(b) : b.motion) {
                    return doHandleBinding(cm, b)
                }
            })
    } else {
        return dispatchKey(cm, name, e, function (b) {
            return doHandleBinding(cm, b);
        })
    }
}

// Handle a key from the keypress event
function handleCharBinding(cm, e, ch) {
    return dispatchKey(cm, "'" + ch + "'", e, function (b) {
        return doHandleBinding(cm, b, true);
    })
}

var lastStoppedKey = null;

function onKeyDown(e) {
    var cm = this;
    cm.curOp.focus = activeElt();
    if (signalDOMEvent(cm, e)) {
        return
    }
    // IE does strange things with escape.
    if (ie && ie_version < 11 && e.keyCode == 27) {
        e.returnValue = false;
    }
    var code = e.keyCode;
    cm.display.shift = code == 16 || e.shiftKey;
    var handled = handleKeyBinding(cm, e);
    if (presto) {
        lastStoppedKey = handled ? code : null;
        // Opera has no cut event... we try to at least catch the key combo
        if (!handled && code == 88 && !hasCopyEvent && (mac ? e.metaKey : e.ctrlKey)) {
            cm.replaceSelection("", null, "cut");
        }
    }

    // Turn mouse into crosshair when Alt is held on Mac.
    if (code == 18 && !/\bCodeMirror-crosshair\b/.test(cm.display.lineDiv.className)) {
        showCrossHair(cm);
    }
}

function showCrossHair(cm) {
    var lineDiv = cm.display.lineDiv;
    addClass(lineDiv, "CodeMirror-crosshair");

    function up(e) {
        if (e.keyCode == 18 || !e.altKey) {
            rmClass(lineDiv, "CodeMirror-crosshair");
            off(document, "keyup", up);
            off(document, "mouseover", up);
        }
    }

    on(document, "keyup", up);
    on(document, "mouseover", up);
}

function onKeyUp(e) {
    if (e.keyCode == 16) {
        this.doc.sel.shift = false;
    }
    signalDOMEvent(this, e);
}

function onKeyPress(e) {
    var cm = this;
    if (eventInWidget(cm.display, e) || signalDOMEvent(cm, e) || e.ctrlKey && !e.altKey || mac && e.metaKey) {
        return
    }
    var keyCode = e.keyCode, charCode = e.charCode;
    if (presto && keyCode == lastStoppedKey) {
        lastStoppedKey = null;
        e_preventDefault(e);
        return
    }
    if ((presto && (!e.which || e.which < 10)) && handleKeyBinding(cm, e)) {
        return
    }
    var ch = String.fromCharCode(charCode == null ? keyCode : charCode);
    // Some browsers fire keypress events for backspace
    if (ch == "\x08") {
        return
    }
    if (handleCharBinding(cm, e, ch)) {
        return
    }
    cm.display.input.onKeyPress(e);
}

var DOUBLECLICK_DELAY = 400;

var PastClick = function (time, pos, button) {
    this.time = time;
    this.pos = pos;
    this.button = button;
};

PastClick.prototype.compare = function (time, pos, button) {
    return this.time + DOUBLECLICK_DELAY > time &&
        cmp(pos, this.pos) == 0 && button == this.button
};

var lastClick, lastDoubleClick;

function clickRepeat(pos, button) {
    var now = +new Date;
    if (lastDoubleClick && lastDoubleClick.compare(now, pos, button)) {
        lastClick = lastDoubleClick = null;
        return "triple"
    } else if (lastClick && lastClick.compare(now, pos, button)) {
        lastDoubleClick = new PastClick(now, pos, button);
        lastClick = null;
        return "double"
    } else {
        lastClick = new PastClick(now, pos, button);
        lastDoubleClick = null;
        return "single"
    }
}

// A mouse down can be a single click, double click, triple click,
// start of selection drag, start of text drag, new cursor
// (ctrl-click), rectangle drag (alt-drag), or xwin
// middle-click-paste. Or it might be a click on something we should
// not interfere with, such as a scrollbar or widget.
function onMouseDown(e) {
    var cm = this, display = cm.display;
    if (signalDOMEvent(cm, e) || display.activeTouch && display.input.supportsTouch()) {
        return
    }
    display.input.ensurePolled();
    display.shift = e.shiftKey;

    if (eventInWidget(display, e)) {
        if (!webkit) {
            // Briefly turn off draggability, to allow widgets to do
            // normal dragging things.
            display.scroller.draggable = false;
            setTimeout(function () {
                return display.scroller.draggable = true;
            }, 100);
        }
        return
    }
    if (clickInGutter(cm, e)) {
        return
    }
    var pos = posFromMouse(cm, e), button = e_button(e), repeat = pos ? clickRepeat(pos, button) : "single";
    window.focus();

    // #3261: make sure, that we're not starting a second selection
    if (button == 1 && cm.state.selectingText) {
        cm.state.selectingText(e);
    }

    if (pos && handleMappedButton(cm, button, pos, repeat, e)) {
        return
    }

    if (button == 1) {
        if (pos) {
            leftButtonDown(cm, pos, repeat, e);
        } else if (e_target(e) == display.scroller) {
            e_preventDefault(e);
        }
    } else if (button == 2) {
        if (pos) {
            extendSelection(cm.doc, pos);
        }
        setTimeout(function () {
            return display.input.focus();
        }, 20);
    } else if (button == 3) {
        if (captureRightClick) {
            cm.display.input.onContextMenu(e);
        } else {
            delayBlurEvent(cm);
        }
    }
}

function handleMappedButton(cm, button, pos, repeat, event) {
    var name = "Click";
    if (repeat == "double") {
        name = "Double" + name;
    } else if (repeat == "triple") {
        name = "Triple" + name;
    }
    name = (button == 1 ? "Left" : button == 2 ? "Middle" : "Right") + name;

    return dispatchKey(cm, addModifierNames(name, event), event, function (bound) {
        if (typeof bound == "string") {
            bound = commands[bound];
        }
        if (!bound) {
            return false
        }
        var done = false;
        try {
            if (cm.isReadOnly()) {
                cm.state.suppressEdits = true;
            }
            done = bound(cm, pos) != Pass;
        } finally {
            cm.state.suppressEdits = false;
        }
        return done
    })
}

function configureMouse(cm, repeat, event) {
    var option = cm.getOption("configureMouse");
    var value = option ? option(cm, repeat, event) : {};
    if (value.unit == null) {
        var rect = chromeOS ? event.shiftKey && event.metaKey : event.altKey;
        value.unit = rect ? "rectangle" : repeat == "single" ? "char" : repeat == "double" ? "word" : "line";
    }
    if (value.extend == null || cm.doc.extend) {
        value.extend = cm.doc.extend || event.shiftKey;
    }
    if (value.addNew == null) {
        value.addNew = mac ? event.metaKey : event.ctrlKey;
    }
    if (value.moveOnDrag == null) {
        value.moveOnDrag = !(mac ? event.altKey : event.ctrlKey);
    }
    return value
}

function leftButtonDown(cm, pos, repeat, event) {
    if (ie) {
        setTimeout(bind(ensureFocus, cm), 0);
    } else {
        cm.curOp.focus = activeElt();
    }

    var behavior = configureMouse(cm, repeat, event);

    var sel = cm.doc.sel, contained;
    if (cm.options.dragDrop && dragAndDrop && !cm.isReadOnly() &&
        repeat == "single" && (contained = sel.contains(pos)) > -1 &&
        (cmp((contained = sel.ranges[contained]).from(), pos) < 0 || pos.xRel > 0) &&
        (cmp(contained.to(), pos) > 0 || pos.xRel < 0)) {
        leftButtonStartDrag(cm, event, pos, behavior);
    } else {
        leftButtonSelect(cm, event, pos, behavior);
    }
}

// Start a text drag. When it ends, see if any dragging actually
// happen, and treat as a click if it didn't.
function leftButtonStartDrag(cm, event, pos, behavior) {
    var display = cm.display, moved = false;
    var dragEnd = operation(cm, function (e) {
        if (webkit) {
            display.scroller.draggable = false;
        }
        cm.state.draggingText = false;
        off(display.wrapper.ownerDocument, "mouseup", dragEnd);
        off(display.wrapper.ownerDocument, "mousemove", mouseMove);
        off(display.scroller, "dragstart", dragStart);
        off(display.scroller, "drop", dragEnd);
        if (!moved) {
            e_preventDefault(e);
            if (!behavior.addNew) {
                extendSelection(cm.doc, pos, null, null, behavior.extend);
            }
            // Work around unexplainable focus problem in IE9 (#2127) and Chrome (#3081)
            if (webkit || ie && ie_version == 9) {
                setTimeout(function () {
                    display.wrapper.ownerDocument.body.focus();
                    display.input.focus();
                }, 20);
            } else {
                display.input.focus();
            }
        }
    });
    var mouseMove = function (e2) {
        moved = moved || Math.abs(event.clientX - e2.clientX) + Math.abs(event.clientY - e2.clientY) >= 10;
    };
    var dragStart = function () {
        return moved = true;
    };
    // Let the drag handler handle this.
    if (webkit) {
        display.scroller.draggable = true;
    }
    cm.state.draggingText = dragEnd;
    dragEnd.copy = !behavior.moveOnDrag;
    // IE's approach to draggable
    if (display.scroller.dragDrop) {
        display.scroller.dragDrop();
    }
    on(display.wrapper.ownerDocument, "mouseup", dragEnd);
    on(display.wrapper.ownerDocument, "mousemove", mouseMove);
    on(display.scroller, "dragstart", dragStart);
    on(display.scroller, "drop", dragEnd);

    delayBlurEvent(cm);
    setTimeout(function () {
        return display.input.focus();
    }, 20);
}

function rangeForUnit(cm, pos, unit) {
    if (unit == "char") {
        return new Range(pos, pos)
    }
    if (unit == "word") {
        return cm.findWordAt(pos)
    }
    if (unit == "line") {
        return new Range(Pos(pos.line, 0), clipPos(cm.doc, Pos(pos.line + 1, 0)))
    }
    var result = unit(cm, pos);
    return new Range(result.from, result.to)
}

// Normal selection, as opposed to text dragging.
function leftButtonSelect(cm, event, start, behavior) {
    var display = cm.display, doc = cm.doc;
    e_preventDefault(event);

    var ourRange, ourIndex, startSel = doc.sel, ranges = startSel.ranges;
    if (behavior.addNew && !behavior.extend) {
        ourIndex = doc.sel.contains(start);
        if (ourIndex > -1) {
            ourRange = ranges[ourIndex];
        } else {
            ourRange = new Range(start, start);
        }
    } else {
        ourRange = doc.sel.primary();
        ourIndex = doc.sel.primIndex;
    }

    if (behavior.unit == "rectangle") {
        if (!behavior.addNew) {
            ourRange = new Range(start, start);
        }
        start = posFromMouse(cm, event, true, true);
        ourIndex = -1;
    } else {
        var range$$1 = rangeForUnit(cm, start, behavior.unit);
        if (behavior.extend) {
            ourRange = extendRange(ourRange, range$$1.anchor, range$$1.head, behavior.extend);
        } else {
            ourRange = range$$1;
        }
    }

    if (!behavior.addNew) {
        ourIndex = 0;
        setSelection(doc, new Selection([ourRange], 0), sel_mouse);
        startSel = doc.sel;
    } else if (ourIndex == -1) {
        ourIndex = ranges.length;
        setSelection(doc, normalizeSelection(cm, ranges.concat([ourRange]), ourIndex),
            {scroll: false, origin: "*mouse"});
    } else if (ranges.length > 1 && ranges[ourIndex].empty() && behavior.unit == "char" && !behavior.extend) {
        setSelection(doc, normalizeSelection(cm, ranges.slice(0, ourIndex).concat(ranges.slice(ourIndex + 1)), 0),
            {scroll: false, origin: "*mouse"});
        startSel = doc.sel;
    } else {
        replaceOneSelection(doc, ourIndex, ourRange, sel_mouse);
    }

    var lastPos = start;

    function extendTo(pos) {
        if (cmp(lastPos, pos) == 0) {
            return
        }
        lastPos = pos;

        if (behavior.unit == "rectangle") {
            var ranges = [], tabSize = cm.options.tabSize;
            var startCol = countColumn(getLine(doc, start.line).text, start.ch, tabSize);
            var posCol = countColumn(getLine(doc, pos.line).text, pos.ch, tabSize);
            var left = Math.min(startCol, posCol), right = Math.max(startCol, posCol);
            for (var line = Math.min(start.line, pos.line), end = Math.min(cm.lastLine(), Math.max(start.line, pos.line));
                 line <= end; line++) {
                var text = getLine(doc, line).text, leftPos = findColumn(text, left, tabSize);
                if (left == right) {
                    ranges.push(new Range(Pos(line, leftPos), Pos(line, leftPos)));
                } else if (text.length > leftPos) {
                    ranges.push(new Range(Pos(line, leftPos), Pos(line, findColumn(text, right, tabSize))));
                }
            }
            if (!ranges.length) {
                ranges.push(new Range(start, start));
            }
            setSelection(doc, normalizeSelection(cm, startSel.ranges.slice(0, ourIndex).concat(ranges), ourIndex),
                {origin: "*mouse", scroll: false});
            cm.scrollIntoView(pos);
        } else {
            var oldRange = ourRange;
            var range$$1 = rangeForUnit(cm, pos, behavior.unit);
            var anchor = oldRange.anchor, head;
            if (cmp(range$$1.anchor, anchor) > 0) {
                head = range$$1.head;
                anchor = minPos(oldRange.from(), range$$1.anchor);
            } else {
                head = range$$1.anchor;
                anchor = maxPos(oldRange.to(), range$$1.head);
            }
            var ranges$1 = startSel.ranges.slice(0);
            ranges$1[ourIndex] = bidiSimplify(cm, new Range(clipPos(doc, anchor), head));
            setSelection(doc, normalizeSelection(cm, ranges$1, ourIndex), sel_mouse);
        }
    }

    var editorSize = display.wrapper.getBoundingClientRect();
    // Used to ensure timeout re-tries don't fire when another extend
    // happened in the meantime (clearTimeout isn't reliable -- at
    // least on Chrome, the timeouts still happen even when cleared,
    // if the clear happens after their scheduled firing time).
    var counter = 0;

    function extend(e) {
        var curCount = ++counter;
        var cur = posFromMouse(cm, e, true, behavior.unit == "rectangle");
        if (!cur) {
            return
        }
        if (cmp(cur, lastPos) != 0) {
            cm.curOp.focus = activeElt();
            extendTo(cur);
            var visible = visibleLines(display, doc);
            if (cur.line >= visible.to || cur.line < visible.from) {
                setTimeout(operation(cm, function () {
                    if (counter == curCount) {
                        extend(e);
                    }
                }), 150);
            }
        } else {
            var outside = e.clientY < editorSize.top ? -20 : e.clientY > editorSize.bottom ? 20 : 0;
            if (outside) {
                setTimeout(operation(cm, function () {
                    if (counter != curCount) {
                        return
                    }
                    display.scroller.scrollTop += outside;
                    extend(e);
                }), 50);
            }
        }
    }

    function done(e) {
        cm.state.selectingText = false;
        counter = Infinity;
        // If e is null or undefined we interpret this as someone trying
        // to explicitly cancel the selection rather than the user
        // letting go of the mouse button.
        if (e) {
            e_preventDefault(e);
            display.input.focus();
        }
        off(display.wrapper.ownerDocument, "mousemove", move);
        off(display.wrapper.ownerDocument, "mouseup", up);
        doc.history.lastSelOrigin = null;
    }

    var move = operation(cm, function (e) {
        if (e.buttons === 0 || !e_button(e)) {
            done(e);
        } else {
            extend(e);
        }
    });
    var up = operation(cm, done);
    cm.state.selectingText = up;
    on(display.wrapper.ownerDocument, "mousemove", move);
    on(display.wrapper.ownerDocument, "mouseup", up);
}

// Used when mouse-selecting to adjust the anchor to the proper side
// of a bidi jump depending on the visual position of the head.
function bidiSimplify(cm, range$$1) {
    var anchor = range$$1.anchor;
    var head = range$$1.head;
    var anchorLine = getLine(cm.doc, anchor.line);
    if (cmp(anchor, head) == 0 && anchor.sticky == head.sticky) {
        return range$$1
    }
    var order = getOrder(anchorLine);
    if (!order) {
        return range$$1
    }
    var index = getBidiPartAt(order, anchor.ch, anchor.sticky), part = order[index];
    if (part.from != anchor.ch && part.to != anchor.ch) {
        return range$$1
    }
    var boundary = index + ((part.from == anchor.ch) == (part.level != 1) ? 0 : 1);
    if (boundary == 0 || boundary == order.length) {
        return range$$1
    }

    // Compute the relative visual position of the head compared to the
    // anchor (<0 is to the left, >0 to the right)
    var leftSide;
    if (head.line != anchor.line) {
        leftSide = (head.line - anchor.line) * (cm.doc.direction == "ltr" ? 1 : -1) > 0;
    } else {
        var headIndex = getBidiPartAt(order, head.ch, head.sticky);
        var dir = headIndex - index || (head.ch - anchor.ch) * (part.level == 1 ? -1 : 1);
        if (headIndex == boundary - 1 || headIndex == boundary) {
            leftSide = dir < 0;
        } else {
            leftSide = dir > 0;
        }
    }

    var usePart = order[boundary + (leftSide ? -1 : 0)];
    var from = leftSide == (usePart.level == 1);
    var ch = from ? usePart.from : usePart.to, sticky = from ? "after" : "before";
    return anchor.ch == ch && anchor.sticky == sticky ? range$$1 : new Range(new Pos(anchor.line, ch, sticky), head)
}


// Determines whether an event happened in the gutter, and fires the
// handlers for the corresponding event.
function gutterEvent(cm, e, type, prevent) {
    var mX, mY;
    if (e.touches) {
        mX = e.touches[0].clientX;
        mY = e.touches[0].clientY;
    } else {
        try {
            mX = e.clientX;
            mY = e.clientY;
        } catch (e) {
            return false
        }
    }
    if (mX >= Math.floor(cm.display.gutters.getBoundingClientRect().right)) {
        return false
    }
    if (prevent) {
        e_preventDefault(e);
    }

    var display = cm.display;
    var lineBox = display.lineDiv.getBoundingClientRect();

    if (mY > lineBox.bottom || !hasHandler(cm, type)) {
        return e_defaultPrevented(e)
    }
    mY -= lineBox.top - display.viewOffset;

    for (var i = 0; i < cm.display.gutterSpecs.length; ++i) {
        var g = display.gutters.childNodes[i];
        if (g && g.getBoundingClientRect().right >= mX) {
            var line = lineAtHeight(cm.doc, mY);
            var gutter = cm.display.gutterSpecs[i];
            signal(cm, type, cm, line, gutter.className, e);
            return e_defaultPrevented(e)
        }
    }
}

function clickInGutter(cm, e) {
    return gutterEvent(cm, e, "gutterClick", true)
}

// CONTEXT MENU HANDLING

// To make the context menu work, we need to briefly unhide the
// textarea (making it as unobtrusive as possible) to let the
// right-click take effect on it.
function onContextMenu(cm, e) {
    if (eventInWidget(cm.display, e) || contextMenuInGutter(cm, e)) {
        return
    }
    if (signalDOMEvent(cm, e, "contextmenu")) {
        return
    }
    if (!captureRightClick) {
        cm.display.input.onContextMenu(e);
    }
}

function contextMenuInGutter(cm, e) {
    if (!hasHandler(cm, "gutterContextMenu")) {
        return false
    }
    return gutterEvent(cm, e, "gutterContextMenu", false)
}

function themeChanged(cm) {
    cm.display.wrapper.className = cm.display.wrapper.className.replace(/\s*cm-s-\S+/g, "") +
        cm.options.theme.replace(/(^|\s)\s*/g, " cm-s-");
    clearCaches(cm);
}

var Init = {
    toString: function () {
        return "CodeMirror.Init"
    }
};

var defaults = {};
var optionHandlers = {};

function defineOptions(CodeMirror) {
    var optionHandlers = CodeMirror.optionHandlers;

    function option(name, deflt, handle, notOnInit) {
        CodeMirror.defaults[name] = deflt;
        if (handle) {
            optionHandlers[name] =
                notOnInit ? function (cm, val, old) {
                    if (old != Init) {
                        handle(cm, val, old);
                    }
                } : handle;
        }
    }

    CodeMirror.defineOption = option;

    // Passed to option handlers when there is no old value.
    CodeMirror.Init = Init;

    // These two are, on init, called from the constructor because they
    // have to be initialized before the src can start at all.
    option("value", "", function (cm, val) {
        return cm.setValue(val);
    }, true);
    option("mode", null, function (cm, val) {
        cm.doc.modeOption = val;
        loadMode(cm);
    }, true);

    option("indentUnit", 2, loadMode, true);
    option("indentWithTabs", false);
    option("smartIndent", true);
    option("tabSize", 4, function (cm) {
        resetModeState(cm);
        clearCaches(cm);
        regChange(cm);
    }, true);

    option("lineSeparator", null, function (cm, val) {
        cm.doc.lineSep = val;
        if (!val) {
            return
        }
        var newBreaks = [], lineNo = cm.doc.first;
        cm.doc.iter(function (line) {
            for (var pos = 0; ;) {
                var found = line.text.indexOf(val, pos);
                if (found == -1) {
                    break
                }
                pos = found + val.length;
                newBreaks.push(Pos(lineNo, found));
            }
            lineNo++;
        });
        for (var i = newBreaks.length - 1; i >= 0; i--) {
            replaceRange(cm.doc, val, newBreaks[i], Pos(newBreaks[i].line, newBreaks[i].ch + val.length));
        }
    });
    option("specialChars", /[\u0000-\u001f\u007f-\u009f\u00ad\u061c\u200b-\u200f\u2028\u2029\ufeff\ufff9-\ufffc]/g, function (cm, val, old) {
        cm.state.specialChars = new RegExp(val.source + (val.test("\t") ? "" : "|\t"), "g");
        if (old != Init) {
            cm.refresh();
        }
    });
    option("specialCharPlaceholder", defaultSpecialCharPlaceholder, function (cm) {
        return cm.refresh();
    }, true);
    option("electricChars", true);
    option("inputStyle", mobile ? "contenteditable" : "textarea", function () {
        throw new Error("inputStyle can not (yet) be changed in a running src") // FIXME
    }, true);
    option("spellcheck", false, function (cm, val) {
        return cm.getInputField().spellcheck = val;
    }, true);
    option("autocorrect", false, function (cm, val) {
        return cm.getInputField().autocorrect = val;
    }, true);
    option("autocapitalize", false, function (cm, val) {
        return cm.getInputField().autocapitalize = val;
    }, true);
    option("rtlMoveVisually", !windows);
    option("wholeLineUpdateBefore", true);

    option("theme", "default", function (cm) {
        themeChanged(cm);
        updateGutters(cm);
    }, true);
    option("keyMap", "default", function (cm, val, old) {
        var next = getKeyMap(val);
        var prev = old != Init && getKeyMap(old);
        if (prev && prev.detach) {
            prev.detach(cm, next);
        }
        if (next.attach) {
            next.attach(cm, prev || null);
        }
    });
    option("extraKeys", null);
    option("configureMouse", null);

    option("lineWrapping", false, wrappingChanged, true);
    option("gutters", [], function (cm, val) {
        cm.display.gutterSpecs = getGutters(val, cm.options.lineNumbers);
        updateGutters(cm);
    }, true);
    option("fixedGutter", true, function (cm, val) {
        cm.display.gutters.style.left = val ? compensateForHScroll(cm.display) + "px" : "0";
        cm.refresh();
    }, true);
    option("coverGutterNextToScrollbar", false, function (cm) {
        return updateScrollbars(cm);
    }, true);
    option("scrollbarStyle", "native", function (cm) {
        initScrollbars(cm);
        updateScrollbars(cm);
        cm.display.scrollbars.setScrollTop(cm.doc.scrollTop);
        cm.display.scrollbars.setScrollLeft(cm.doc.scrollLeft);
    }, true);
    option("lineNumbers", false, function (cm, val) {
        cm.display.gutterSpecs = getGutters(cm.options.gutters, val);
        updateGutters(cm);
    }, true);
    option("firstLineNumber", 1, updateGutters, true);
    option("lineNumberFormatter", function (integer) {
        return integer;
    }, updateGutters, true);
    option("showCursorWhenSelecting", false, updateSelection, true);

    option("resetSelectionOnContextMenu", true);
    option("lineWiseCopyCut", true);
    option("pasteLinesPerSelection", true);
    option("selectionsMayTouch", false);

    option("readOnly", false, function (cm, val) {
        if (val == "nocursor") {
            onBlur(cm);
            cm.display.input.blur();
        }
        cm.display.input.readOnlyChanged(val);
    });
    option("disableInput", false, function (cm, val) {
        if (!val) {
            cm.display.input.reset();
        }
    }, true);
    option("dragDrop", true, dragDropChanged);
    option("allowDropFileTypes", null);

    option("cursorBlinkRate", 530);
    option("cursorScrollMargin", 0);
    option("cursorHeight", 1, updateSelection, true);
    option("singleCursorHeightPerLine", true, updateSelection, true);
    option("workTime", 100);
    option("workDelay", 100);
    option("flattenSpans", true, resetModeState, true);
    option("addModeClass", false, resetModeState, true);
    option("pollInterval", 100);
    option("undoDepth", 200, function (cm, val) {
        return cm.doc.history.undoDepth = val;
    });
    option("historyEventDelay", 1250);
    option("viewportMargin", 10, function (cm) {
        return cm.refresh();
    }, true);
    option("maxHighlightLength", 10000, resetModeState, true);
    option("moveInputWithCursor", true, function (cm, val) {
        if (!val) {
            cm.display.input.resetPosition();
        }
    });

    option("tabindex", null, function (cm, val) {
        return cm.display.input.getField().tabIndex = val || "";
    });
    option("autofocus", null);
    option("direction", "ltr", function (cm, val) {
        return cm.doc.setDirection(val);
    }, true);
    option("phrases", null);
}

function dragDropChanged(cm, value, old) {
    var wasOn = old && old != Init;
    if (!value != !wasOn) {
        var funcs = cm.display.dragFunctions;
        var toggle = value ? on : off;
        toggle(cm.display.scroller, "dragstart", funcs.start);
        toggle(cm.display.scroller, "dragenter", funcs.enter);
        toggle(cm.display.scroller, "dragover", funcs.over);
        toggle(cm.display.scroller, "dragleave", funcs.leave);
        toggle(cm.display.scroller, "drop", funcs.drop);
    }
}

function wrappingChanged(cm) {
    if (cm.options.lineWrapping) {
        addClass(cm.display.wrapper, "CodeMirror-wrap");
        cm.display.sizer.style.minWidth = "";
        cm.display.sizerWidth = null;
    } else {
        rmClass(cm.display.wrapper, "CodeMirror-wrap");
        findMaxLine(cm);
    }
    estimateLineHeights(cm);
    regChange(cm);
    clearCaches(cm);
    setTimeout(function () {
        return updateScrollbars(cm);
    }, 100);
}

// A CodeMirror instance represents an src. This is the object
// that user code is usually dealing with.

function CodeMirror(place, options) {
    var this$1 = this;

    if (!(this instanceof CodeMirror)) {
        return new CodeMirror(place, options)
    }

    this.options = options = options ? copyObj(options) : {};
    // Determine effective options based on given values and defaults.
    copyObj(defaults, options, false);

    var doc = options.value;
    if (typeof doc == "string") {
        doc = new Doc(doc, options.mode, null, options.lineSeparator, options.direction);
    } else if (options.mode) {
        doc.modeOption = options.mode;
    }
    this.doc = doc;

    var input = new CodeMirror.inputStyles[options.inputStyle](this);
    var display = this.display = new Display(place, doc, input, options);
    display.wrapper.CodeMirror = this;
    themeChanged(this);
    if (options.lineWrapping) {
        this.display.wrapper.className += " CodeMirror-wrap";
    }
    initScrollbars(this);

    this.state = {
        keyMaps: [],  // stores maps added by addKeyMap
        overlays: [], // highlighting overlays, as added by addOverlay
        modeGen: 0,   // bumped when mode/overlay changes, used to invalidate highlighting info
        overwrite: false,
        delayingBlurEvent: false,
        focused: false,
        suppressEdits: false, // used to disable editing during key handlers when in readOnly mode
        pasteIncoming: -1, cutIncoming: -1, // help recognize paste/cut edits in input.poll
        selectingText: false,
        draggingText: false,
        highlight: new Delayed(), // stores highlight worker timeout
        keySeq: null,  // Unfinished key sequence
        specialChars: null
    };

    if (options.autofocus && !mobile) {
        display.input.focus();
    }

    // Override magic textarea content restore that IE sometimes does
    // on our hidden textarea on reload
    if (ie && ie_version < 11) {
        setTimeout(function () {
            return this$1.display.input.reset(true);
        }, 20);
    }

    registerEventHandlers(this);
    ensureGlobalHandlers();

    startOperation(this);
    this.curOp.forceUpdate = true;
    attachDoc(this, doc);

    if ((options.autofocus && !mobile) || this.hasFocus()) {
        setTimeout(bind(onFocus, this), 20);
    } else {
        onBlur(this);
    }

    for (var opt in optionHandlers) {
        if (optionHandlers.hasOwnProperty(opt)) {
            optionHandlers[opt](this$1, options[opt], Init);
        }
    }
    maybeUpdateLineNumberWidth(this);
    if (options.finishInit) {
        options.finishInit(this);
    }
    for (var i = 0; i < initHooks.length; ++i) {
        initHooks[i](this$1);
    }
    endOperation(this);
    // Suppress optimizelegibility in Webkit, since it breaks text
    // measuring on line wrapping boundaries.
    if (webkit && options.lineWrapping &&
        getComputedStyle(display.lineDiv).textRendering == "optimizelegibility") {
        display.lineDiv.style.textRendering = "auto";
    }
    if (options.onload) {
        options.onload(this);
    }
}

// The default configuration options.
CodeMirror.defaults = defaults;
// Functions to run when options are changed.
CodeMirror.optionHandlers = optionHandlers;

// Attach the necessary event handlers when initializing the src
function registerEventHandlers(cm) {
    var d = cm.display;
    on(d.scroller, "mousedown", operation(cm, onMouseDown));
    // Older IE's will not fire a second mousedown for a double click
    if (ie && ie_version < 11) {
        on(d.scroller, "dblclick", operation(cm, function (e) {
            if (signalDOMEvent(cm, e)) {
                return
            }
            var pos = posFromMouse(cm, e);
            if (!pos || clickInGutter(cm, e) || eventInWidget(cm.display, e)) {
                return
            }
            e_preventDefault(e);
            var word = cm.findWordAt(pos);
            extendSelection(cm.doc, word.anchor, word.head);
        }));
    } else {
        on(d.scroller, "dblclick", function (e) {
            return signalDOMEvent(cm, e) || e_preventDefault(e);
        });
    }
    // Some browsers fire contextmenu *after* opening the menu, at
    // which point we can't mess with it anymore. Context menu is
    // handled in onMouseDown for these browsers.
    on(d.scroller, "contextmenu", function (e) {
        return onContextMenu(cm, e);
    });

    // Used to suppress mouse event handling when a touch happens
    var touchFinished, prevTouch = {end: 0};

    function finishTouch() {
        if (d.activeTouch) {
            touchFinished = setTimeout(function () {
                return d.activeTouch = null;
            }, 1000);
            prevTouch = d.activeTouch;
            prevTouch.end = +new Date;
        }
    }

    function isMouseLikeTouchEvent(e) {
        if (e.touches.length != 1) {
            return false
        }
        var touch = e.touches[0];
        return touch.radiusX <= 1 && touch.radiusY <= 1
    }

    function farAway(touch, other) {
        if (other.left == null) {
            return true
        }
        var dx = other.left - touch.left, dy = other.top - touch.top;
        return dx * dx + dy * dy > 20 * 20
    }

    on(d.scroller, "touchstart", function (e) {
        if (!signalDOMEvent(cm, e) && !isMouseLikeTouchEvent(e) && !clickInGutter(cm, e)) {
            d.input.ensurePolled();
            clearTimeout(touchFinished);
            var now = +new Date;
            d.activeTouch = {
                start: now, moved: false,
                prev: now - prevTouch.end <= 300 ? prevTouch : null
            };
            if (e.touches.length == 1) {
                d.activeTouch.left = e.touches[0].pageX;
                d.activeTouch.top = e.touches[0].pageY;
            }
        }
    });
    on(d.scroller, "touchmove", function () {
        if (d.activeTouch) {
            d.activeTouch.moved = true;
        }
    });
    on(d.scroller, "touchend", function (e) {
        var touch = d.activeTouch;
        if (touch && !eventInWidget(d, e) && touch.left != null &&
            !touch.moved && new Date - touch.start < 300) {
            var pos = cm.coordsChar(d.activeTouch, "page"), range;
            if (!touch.prev || farAway(touch, touch.prev)) // Single tap
            {
                range = new Range(pos, pos);
            } else if (!touch.prev.prev || farAway(touch, touch.prev.prev)) // Double tap
            {
                range = cm.findWordAt(pos);
            } else // Triple tap
            {
                range = new Range(Pos(pos.line, 0), clipPos(cm.doc, Pos(pos.line + 1, 0)));
            }
            cm.setSelection(range.anchor, range.head);
            cm.focus();
            e_preventDefault(e);
        }
        finishTouch();
    });
    on(d.scroller, "touchcancel", finishTouch);

    // Sync scrolling between fake scrollbars and real scrollable
    // area, ensure viewport is updated when scrolling.
    on(d.scroller, "scroll", function () {
        if (d.scroller.clientHeight) {
            updateScrollTop(cm, d.scroller.scrollTop);
            setScrollLeft(cm, d.scroller.scrollLeft, true);
            signal(cm, "scroll", cm);
        }
    });

    // Listen to wheel events in order to try and update the viewport on time.
    on(d.scroller, "mousewheel", function (e) {
        return onScrollWheel(cm, e);
    });
    on(d.scroller, "DOMMouseScroll", function (e) {
        return onScrollWheel(cm, e);
    });

    // Prevent wrapper from ever scrolling
    on(d.wrapper, "scroll", function () {
        return d.wrapper.scrollTop = d.wrapper.scrollLeft = 0;
    });
    d.dragFunctions = {
        enter: function (e) {
            if (!signalDOMEvent(cm, e)) {
                e_stop(e);
            }
        },
        over: function (e) {
            if (!signalDOMEvent(cm, e)) {
                onDragOver(cm, e);
                e_stop(e);
            }
        },
        start: function (e) {
            return onDragStart(cm, e);
        },
        drop: operation(cm, onDrop),
        leave: function (e) {
            if (!signalDOMEvent(cm, e)) {
                clearDragCursor(cm);
            }
        }
    };

    var inp = d.input.getField();
    on(inp, "keyup", function (e) {
        return onKeyUp.call(cm, e);
    });
    on(inp, "keydown", operation(cm, onKeyDown));
    on(inp, "keypress", operation(cm, onKeyPress));
    on(inp, "focus", function (e) {
        return onFocus(cm, e);
    });
    on(inp, "blur", function (e) {
        return onBlur(cm, e);
    });
}

var initHooks = [];
CodeMirror.defineInitHook = function (f) {
    return initHooks.push(f);
};

// Indent the given line. The how parameter can be "smart",
// "add"/null, "subtract", or "prev". When aggressive is false
// (typically set to true for forced single-line indents), empty
// lines are not indented, and places where the mode returns Pass
// are left alone.
function indentLine(cm, n, how, aggressive) {
    var doc = cm.doc, state;
    if (how == null) {
        how = "add";
    }
    if (how == "smart") {
        // Fall back to "prev" when the mode doesn't have an indentation
        // method.
        if (!doc.mode.indent) {
            how = "prev";
        } else {
            state = getContextBefore(cm, n).state;
        }
    }

    var tabSize = cm.options.tabSize;
    var line = getLine(doc, n), curSpace = countColumn(line.text, null, tabSize);
    if (line.stateAfter) {
        line.stateAfter = null;
    }
    var curSpaceString = line.text.match(/^\s*/)[0], indentation;
    if (!aggressive && !/\S/.test(line.text)) {
        indentation = 0;
        how = "not";
    } else if (how == "smart") {
        indentation = doc.mode.indent(state, line.text.slice(curSpaceString.length), line.text);
        if (indentation == Pass || indentation > 150) {
            if (!aggressive) {
                return
            }
            how = "prev";
        }
    }
    if (how == "prev") {
        if (n > doc.first) {
            indentation = countColumn(getLine(doc, n - 1).text, null, tabSize);
        } else {
            indentation = 0;
        }
    } else if (how == "add") {
        indentation = curSpace + cm.options.indentUnit;
    } else if (how == "subtract") {
        indentation = curSpace - cm.options.indentUnit;
    } else if (typeof how == "number") {
        indentation = curSpace + how;
    }
    indentation = Math.max(0, indentation);

    var indentString = "", pos = 0;
    if (cm.options.indentWithTabs) {
        for (var i = Math.floor(indentation / tabSize); i; --i) {
            pos += tabSize;
            indentString += "\t";
        }
    }
    if (pos < indentation) {
        indentString += spaceStr(indentation - pos);
    }

    if (indentString != curSpaceString) {
        replaceRange(doc, indentString, Pos(n, 0), Pos(n, curSpaceString.length), "+input");
        line.stateAfter = null;
        return true
    } else {
        // Ensure that, if the cursor was in the whitespace at the start
        // of the line, it is moved to the end of that space.
        for (var i$1 = 0; i$1 < doc.sel.ranges.length; i$1++) {
            var range = doc.sel.ranges[i$1];
            if (range.head.line == n && range.head.ch < curSpaceString.length) {
                var pos$1 = Pos(n, curSpaceString.length);
                replaceOneSelection(doc, i$1, new Range(pos$1, pos$1));
                break
            }
        }
    }
}

// This will be set to a {lineWise: bool, text: [string]} object, so
// that, when pasting, we know what kind of selections the copied
// text was made out of.
var lastCopied = null;

function setLastCopied(newLastCopied) {
    lastCopied = newLastCopied;
}

function applyTextInput(cm, inserted, deleted, sel, origin) {
    var doc = cm.doc;
    cm.display.shift = false;
    if (!sel) {
        sel = doc.sel;
    }

    var recent = +new Date - 200;
    var paste = origin == "paste" || cm.state.pasteIncoming > recent;
    var textLines = splitLinesAuto(inserted), multiPaste = null;
    // When pasting N lines into N selections, insert one line per selection
    if (paste && sel.ranges.length > 1) {
        if (lastCopied && lastCopied.text.join("\n") == inserted) {
            if (sel.ranges.length % lastCopied.text.length == 0) {
                multiPaste = [];
                for (var i = 0; i < lastCopied.text.length; i++) {
                    multiPaste.push(doc.splitLines(lastCopied.text[i]));
                }
            }
        } else if (textLines.length == sel.ranges.length && cm.options.pasteLinesPerSelection) {
            multiPaste = map(textLines, function (l) {
                return [l];
            });
        }
    }

    var updateInput = cm.curOp.updateInput;
    // Normal behavior is to insert the new text into every selection
    for (var i$1 = sel.ranges.length - 1; i$1 >= 0; i$1--) {
        var range$$1 = sel.ranges[i$1];
        var from = range$$1.from(), to = range$$1.to();
        if (range$$1.empty()) {
            if (deleted && deleted > 0) // Handle deletion
            {
                from = Pos(from.line, from.ch - deleted);
            } else if (cm.state.overwrite && !paste) // Handle overwrite
            {
                to = Pos(to.line, Math.min(getLine(doc, to.line).text.length, to.ch + lst(textLines).length));
            } else if (paste && lastCopied && lastCopied.lineWise && lastCopied.text.join("\n") == inserted) {
                from = to = Pos(from.line, 0);
            }
        }
        var changeEvent = {
            from: from, to: to, text: multiPaste ? multiPaste[i$1 % multiPaste.length] : textLines,
            origin: origin || (paste ? "paste" : cm.state.cutIncoming > recent ? "cut" : "+input")
        };
        makeChange(cm.doc, changeEvent);
        signalLater(cm, "inputRead", cm, changeEvent);
    }
    if (inserted && !paste) {
        triggerElectric(cm, inserted);
    }

    ensureCursorVisible(cm);
    if (cm.curOp.updateInput < 2) {
        cm.curOp.updateInput = updateInput;
    }
    cm.curOp.typing = true;
    cm.state.pasteIncoming = cm.state.cutIncoming = -1;
}

function handlePaste(e, cm) {
    var pasted = e.clipboardData && e.clipboardData.getData("Text");
    if (pasted) {
        e.preventDefault();
        if (!cm.isReadOnly() && !cm.options.disableInput) {
            runInOp(cm, function () {
                return applyTextInput(cm, pasted, 0, null, "paste");
            });
        }
        return true
    }
}

function triggerElectric(cm, inserted) {
    // When an 'electric' character is inserted, immediately trigger a reindent
    if (!cm.options.electricChars || !cm.options.smartIndent) {
        return
    }
    var sel = cm.doc.sel;

    for (var i = sel.ranges.length - 1; i >= 0; i--) {
        var range$$1 = sel.ranges[i];
        if (range$$1.head.ch > 100 || (i && sel.ranges[i - 1].head.line == range$$1.head.line)) {
            continue
        }
        var mode = cm.getModeAt(range$$1.head);
        var indented = false;
        if (mode.electricChars) {
            for (var j = 0; j < mode.electricChars.length; j++) {
                if (inserted.indexOf(mode.electricChars.charAt(j)) > -1) {
                    indented = indentLine(cm, range$$1.head.line, "smart");
                    break
                }
            }
        } else if (mode.electricInput) {
            if (mode.electricInput.test(getLine(cm.doc, range$$1.head.line).text.slice(0, range$$1.head.ch))) {
                indented = indentLine(cm, range$$1.head.line, "smart");
            }
        }
        if (indented) {
            signalLater(cm, "electricInput", cm, range$$1.head.line);
        }
    }
}

function copyableRanges(cm) {
    var text = [], ranges = [];
    for (var i = 0; i < cm.doc.sel.ranges.length; i++) {
        var line = cm.doc.sel.ranges[i].head.line;
        var lineRange = {anchor: Pos(line, 0), head: Pos(line + 1, 0)};
        ranges.push(lineRange);
        text.push(cm.getRange(lineRange.anchor, lineRange.head));
    }
    return {text: text, ranges: ranges}
}

function disableBrowserMagic(field, spellcheck, autocorrect, autocapitalize) {
    field.setAttribute("autocorrect", autocorrect ? "" : "off");
    field.setAttribute("autocapitalize", autocapitalize ? "" : "off");
    field.setAttribute("spellcheck", !!spellcheck);
}

function hiddenTextarea() {
    var te = elt("textarea", null, null, "position: absolute; bottom: -1em; padding: 0; width: 1px; height: 1em; outline: none");
    var div = elt("div", [te], null, "overflow: hidden; position: relative; width: 3px; height: 0px;");
    // The textarea is kept positioned near the cursor to prevent the
    // fact that it'll be scrolled into view on input from scrolling
    // our fake cursor out of view. On webkit, when wrap=off, paste is
    // very slow. So make the area wide instead.
    if (webkit) {
        te.style.width = "1000px";
    } else {
        te.setAttribute("wrap", "off");
    }
    // If border: 0; -- iOS fails to open keyboard (issue #1287)
    if (ios) {
        te.style.border = "1px solid black";
    }
    disableBrowserMagic(te);
    return div
}

// The publicly visible API. Note that methodOp(f) means
// 'wrap f in an operation, performed on its `this` parameter'.

// This is not the complete set of src methods. Most of the
// methods defined on the Doc type are also injected into
// CodeMirror.prototype, for backwards compatibility and
// convenience.

function addEditorMethods(CodeMirror) {
    var optionHandlers = CodeMirror.optionHandlers;

    var helpers = CodeMirror.helpers = {};

    CodeMirror.prototype = {
        constructor: CodeMirror,
        focus: function () {
            window.focus();
            this.display.input.focus();
        },

        setOption: function (option, value) {
            var options = this.options, old = options[option];
            if (options[option] == value && option != "mode") {
                return
            }
            options[option] = value;
            if (optionHandlers.hasOwnProperty(option)) {
                operation(this, optionHandlers[option])(this, value, old);
            }
            signal(this, "optionChange", this, option);
        },

        getOption: function (option) {
            return this.options[option]
        },
        getDoc: function () {
            return this.doc
        },

        addKeyMap: function (map$$1, bottom) {
            this.state.keyMaps[bottom ? "push" : "unshift"](getKeyMap(map$$1));
        },
        removeKeyMap: function (map$$1) {
            var maps = this.state.keyMaps;
            for (var i = 0; i < maps.length; ++i) {
                if (maps[i] == map$$1 || maps[i].name == map$$1) {
                    maps.splice(i, 1);
                    return true
                }
            }
        },

        addOverlay: methodOp(function (spec, options) {
            var mode = spec.token ? spec : CodeMirror.getMode(this.options, spec);
            if (mode.startState) {
                throw new Error("Overlays may not be stateful.")
            }
            insertSorted(this.state.overlays,
                {
                    mode: mode, modeSpec: spec, opaque: options && options.opaque,
                    priority: (options && options.priority) || 0
                },
                function (overlay) {
                    return overlay.priority;
                });
            this.state.modeGen++;
            regChange(this);
        }),
        removeOverlay: methodOp(function (spec) {
            var this$1 = this;

            var overlays = this.state.overlays;
            for (var i = 0; i < overlays.length; ++i) {
                var cur = overlays[i].modeSpec;
                if (cur == spec || typeof spec == "string" && cur.name == spec) {
                    overlays.splice(i, 1);
                    this$1.state.modeGen++;
                    regChange(this$1);
                    return
                }
            }
        }),

        indentLine: methodOp(function (n, dir, aggressive) {
            if (typeof dir != "string" && typeof dir != "number") {
                if (dir == null) {
                    dir = this.options.smartIndent ? "smart" : "prev";
                } else {
                    dir = dir ? "add" : "subtract";
                }
            }
            if (isLine(this.doc, n)) {
                indentLine(this, n, dir, aggressive);
            }
        }),
        indentSelection: methodOp(function (how) {
            var this$1 = this;

            var ranges = this.doc.sel.ranges, end = -1;
            for (var i = 0; i < ranges.length; i++) {
                var range$$1 = ranges[i];
                if (!range$$1.empty()) {
                    var from = range$$1.from(), to = range$$1.to();
                    var start = Math.max(end, from.line);
                    end = Math.min(this$1.lastLine(), to.line - (to.ch ? 0 : 1)) + 1;
                    for (var j = start; j < end; ++j) {
                        indentLine(this$1, j, how);
                    }
                    var newRanges = this$1.doc.sel.ranges;
                    if (from.ch == 0 && ranges.length == newRanges.length && newRanges[i].from().ch > 0) {
                        replaceOneSelection(this$1.doc, i, new Range(from, newRanges[i].to()), sel_dontScroll);
                    }
                } else if (range$$1.head.line > end) {
                    indentLine(this$1, range$$1.head.line, how, true);
                    end = range$$1.head.line;
                    if (i == this$1.doc.sel.primIndex) {
                        ensureCursorVisible(this$1);
                    }
                }
            }
        }),

        // Fetch the parser token for a given character. Useful for hacks
        // that want to inspect the mode state (say, for completion).
        getTokenAt: function (pos, precise) {
            return takeToken(this, pos, precise)
        },

        getLineTokens: function (line, precise) {
            return takeToken(this, Pos(line), precise, true)
        },

        getTokenTypeAt: function (pos) {
            pos = clipPos(this.doc, pos);
            var styles = getLineStyles(this, getLine(this.doc, pos.line));
            var before = 0, after = (styles.length - 1) / 2, ch = pos.ch;
            var type;
            if (ch == 0) {
                type = styles[2];
            } else {
                for (; ;) {
                    var mid = (before + after) >> 1;
                    if ((mid ? styles[mid * 2 - 1] : 0) >= ch) {
                        after = mid;
                    } else if (styles[mid * 2 + 1] < ch) {
                        before = mid + 1;
                    } else {
                        type = styles[mid * 2 + 2];
                        break
                    }
                }
            }
            var cut = type ? type.indexOf("overlay ") : -1;
            return cut < 0 ? type : cut == 0 ? null : type.slice(0, cut - 1)
        },

        getModeAt: function (pos) {
            var mode = this.doc.mode;
            if (!mode.innerMode) {
                return mode
            }
            return CodeMirror.innerMode(mode, this.getTokenAt(pos).state).mode
        },

        getHelper: function (pos, type) {
            return this.getHelpers(pos, type)[0]
        },

        getHelpers: function (pos, type) {
            var this$1 = this;

            var found = [];
            if (!helpers.hasOwnProperty(type)) {
                return found
            }
            var help = helpers[type], mode = this.getModeAt(pos);
            if (typeof mode[type] == "string") {
                if (help[mode[type]]) {
                    found.push(help[mode[type]]);
                }
            } else if (mode[type]) {
                for (var i = 0; i < mode[type].length; i++) {
                    var val = help[mode[type][i]];
                    if (val) {
                        found.push(val);
                    }
                }
            } else if (mode.helperType && help[mode.helperType]) {
                found.push(help[mode.helperType]);
            } else if (help[mode.name]) {
                found.push(help[mode.name]);
            }
            for (var i$1 = 0; i$1 < help._global.length; i$1++) {
                var cur = help._global[i$1];
                if (cur.pred(mode, this$1) && indexOf(found, cur.val) == -1) {
                    found.push(cur.val);
                }
            }
            return found
        },

        getStateAfter: function (line, precise) {
            var doc = this.doc;
            line = clipLine(doc, line == null ? doc.first + doc.size - 1 : line);
            return getContextBefore(this, line + 1, precise).state
        },

        cursorCoords: function (start, mode) {
            var pos, range$$1 = this.doc.sel.primary();
            if (start == null) {
                pos = range$$1.head;
            } else if (typeof start == "object") {
                pos = clipPos(this.doc, start);
            } else {
                pos = start ? range$$1.from() : range$$1.to();
            }
            return cursorCoords(this, pos, mode || "page")
        },

        charCoords: function (pos, mode) {
            return charCoords(this, clipPos(this.doc, pos), mode || "page")
        },

        coordsChar: function (coords, mode) {
            coords = fromCoordSystem(this, coords, mode || "page");
            return coordsChar(this, coords.left, coords.top)
        },

        lineAtHeight: function (height, mode) {
            height = fromCoordSystem(this, {top: height, left: 0}, mode || "page").top;
            return lineAtHeight(this.doc, height + this.display.viewOffset)
        },
        heightAtLine: function (line, mode, includeWidgets) {
            var end = false, lineObj;
            if (typeof line == "number") {
                var last = this.doc.first + this.doc.size - 1;
                if (line < this.doc.first) {
                    line = this.doc.first;
                } else if (line > last) {
                    line = last;
                    end = true;
                }
                lineObj = getLine(this.doc, line);
            } else {
                lineObj = line;
            }
            return intoCoordSystem(this, lineObj, {top: 0, left: 0}, mode || "page", includeWidgets || end).top +
                (end ? this.doc.height - heightAtLine(lineObj) : 0)
        },

        defaultTextHeight: function () {
            return textHeight(this.display)
        },
        defaultCharWidth: function () {
            return charWidth(this.display)
        },

        getViewport: function () {
            return {from: this.display.viewFrom, to: this.display.viewTo}
        },

        addWidget: function (pos, node, scroll, vert, horiz) {
            var display = this.display;
            pos = cursorCoords(this, clipPos(this.doc, pos));
            var top = pos.bottom, left = pos.left;
            node.style.position = "absolute";
            node.setAttribute("cm-ignore-events", "true");
            this.display.input.setUneditable(node);
            display.sizer.appendChild(node);
            if (vert == "over") {
                top = pos.top;
            } else if (vert == "above" || vert == "near") {
                var vspace = Math.max(display.wrapper.clientHeight, this.doc.height),
                    hspace = Math.max(display.sizer.clientWidth, display.lineSpace.clientWidth);
                // Default to positioning above (if specified and possible); otherwise default to positioning below
                if ((vert == 'above' || pos.bottom + node.offsetHeight > vspace) && pos.top > node.offsetHeight) {
                    top = pos.top - node.offsetHeight;
                } else if (pos.bottom + node.offsetHeight <= vspace) {
                    top = pos.bottom;
                }
                if (left + node.offsetWidth > hspace) {
                    left = hspace - node.offsetWidth;
                }
            }
            node.style.top = top + "px";
            node.style.left = node.style.right = "";
            if (horiz == "right") {
                left = display.sizer.clientWidth - node.offsetWidth;
                node.style.right = "0px";
            } else {
                if (horiz == "left") {
                    left = 0;
                } else if (horiz == "middle") {
                    left = (display.sizer.clientWidth - node.offsetWidth) / 2;
                }
                node.style.left = left + "px";
            }
            if (scroll) {
                scrollIntoView(this, {
                    left: left,
                    top: top,
                    right: left + node.offsetWidth,
                    bottom: top + node.offsetHeight
                });
            }
        },

        triggerOnKeyDown: methodOp(onKeyDown),
        triggerOnKeyPress: methodOp(onKeyPress),
        triggerOnKeyUp: onKeyUp,
        triggerOnMouseDown: methodOp(onMouseDown),

        execCommand: function (cmd) {
            if (commands.hasOwnProperty(cmd)) {
                return commands[cmd].call(null, this)
            }
        },

        triggerElectric: methodOp(function (text) {
            triggerElectric(this, text);
        }),

        findPosH: function (from, amount, unit, visually) {
            var this$1 = this;

            var dir = 1;
            if (amount < 0) {
                dir = -1;
                amount = -amount;
            }
            var cur = clipPos(this.doc, from);
            for (var i = 0; i < amount; ++i) {
                cur = findPosH(this$1.doc, cur, dir, unit, visually);
                if (cur.hitSide) {
                    break
                }
            }
            return cur
        },

        moveH: methodOp(function (dir, unit) {
            var this$1 = this;

            this.extendSelectionsBy(function (range$$1) {
                if (this$1.display.shift || this$1.doc.extend || range$$1.empty()) {
                    return findPosH(this$1.doc, range$$1.head, dir, unit, this$1.options.rtlMoveVisually)
                } else {
                    return dir < 0 ? range$$1.from() : range$$1.to()
                }
            }, sel_move);
        }),

        deleteH: methodOp(function (dir, unit) {
            var sel = this.doc.sel, doc = this.doc;
            if (sel.somethingSelected()) {
                doc.replaceSelection("", null, "+delete");
            } else {
                deleteNearSelection(this, function (range$$1) {
                    var other = findPosH(doc, range$$1.head, dir, unit, false);
                    return dir < 0 ? {from: other, to: range$$1.head} : {from: range$$1.head, to: other}
                });
            }
        }),

        findPosV: function (from, amount, unit, goalColumn) {
            var this$1 = this;

            var dir = 1, x = goalColumn;
            if (amount < 0) {
                dir = -1;
                amount = -amount;
            }
            var cur = clipPos(this.doc, from);
            for (var i = 0; i < amount; ++i) {
                var coords = cursorCoords(this$1, cur, "div");
                if (x == null) {
                    x = coords.left;
                } else {
                    coords.left = x;
                }
                cur = findPosV(this$1, coords, dir, unit);
                if (cur.hitSide) {
                    break
                }
            }
            return cur
        },

        moveV: methodOp(function (dir, unit) {
            var this$1 = this;

            var doc = this.doc, goals = [];
            var collapse = !this.display.shift && !doc.extend && doc.sel.somethingSelected();
            doc.extendSelectionsBy(function (range$$1) {
                if (collapse) {
                    return dir < 0 ? range$$1.from() : range$$1.to()
                }
                var headPos = cursorCoords(this$1, range$$1.head, "div");
                if (range$$1.goalColumn != null) {
                    headPos.left = range$$1.goalColumn;
                }
                goals.push(headPos.left);
                var pos = findPosV(this$1, headPos, dir, unit);
                if (unit == "page" && range$$1 == doc.sel.primary()) {
                    addToScrollTop(this$1, charCoords(this$1, pos, "div").top - headPos.top);
                }
                return pos
            }, sel_move);
            if (goals.length) {
                for (var i = 0; i < doc.sel.ranges.length; i++) {
                    doc.sel.ranges[i].goalColumn = goals[i];
                }
            }
        }),

        // Find the word at the given position (as returned by coordsChar).
        findWordAt: function (pos) {
            var doc = this.doc, line = getLine(doc, pos.line).text;
            var start = pos.ch, end = pos.ch;
            if (line) {
                var helper = this.getHelper(pos, "wordChars");
                if ((pos.sticky == "before" || end == line.length) && start) {
                    --start;
                } else {
                    ++end;
                }
                var startChar = line.charAt(start);
                var check = isWordChar(startChar, helper)
                    ? function (ch) {
                        return isWordChar(ch, helper);
                    }
                    : /\s/.test(startChar) ? function (ch) {
                            return /\s/.test(ch);
                        }
                        : function (ch) {
                            return (!/\s/.test(ch) && !isWordChar(ch));
                        };
                while (start > 0 && check(line.charAt(start - 1))) {
                    --start;
                }
                while (end < line.length && check(line.charAt(end))) {
                    ++end;
                }
            }
            return new Range(Pos(pos.line, start), Pos(pos.line, end))
        },

        toggleOverwrite: function (value) {
            if (value != null && value == this.state.overwrite) {
                return
            }
            if (this.state.overwrite = !this.state.overwrite) {
                addClass(this.display.cursorDiv, "CodeMirror-overwrite");
            } else {
                rmClass(this.display.cursorDiv, "CodeMirror-overwrite");
            }

            signal(this, "overwriteToggle", this, this.state.overwrite);
        },
        hasFocus: function () {
            return this.display.input.getField() == activeElt()
        },
        isReadOnly: function () {
            return !!(this.options.readOnly || this.doc.cantEdit)
        },

        scrollTo: methodOp(function (x, y) {
            scrollToCoords(this, x, y);
        }),
        getScrollInfo: function () {
            var scroller = this.display.scroller;
            return {
                left: scroller.scrollLeft, top: scroller.scrollTop,
                height: scroller.scrollHeight - scrollGap(this) - this.display.barHeight,
                width: scroller.scrollWidth - scrollGap(this) - this.display.barWidth,
                clientHeight: displayHeight(this), clientWidth: displayWidth(this)
            }
        },

        scrollIntoView: methodOp(function (range$$1, margin) {
            if (range$$1 == null) {
                range$$1 = {from: this.doc.sel.primary().head, to: null};
                if (margin == null) {
                    margin = this.options.cursorScrollMargin;
                }
            } else if (typeof range$$1 == "number") {
                range$$1 = {from: Pos(range$$1, 0), to: null};
            } else if (range$$1.from == null) {
                range$$1 = {from: range$$1, to: null};
            }
            if (!range$$1.to) {
                range$$1.to = range$$1.from;
            }
            range$$1.margin = margin || 0;

            if (range$$1.from.line != null) {
                scrollToRange(this, range$$1);
            } else {
                scrollToCoordsRange(this, range$$1.from, range$$1.to, range$$1.margin);
            }
        }),

        setSize: methodOp(function (width, height) {
            var this$1 = this;

            var interpret = function (val) {
                return typeof val == "number" || /^\d+$/.test(String(val)) ? val + "px" : val;
            };
            if (width != null) {
                this.display.wrapper.style.width = interpret(width);
            }
            if (height != null) {
                this.display.wrapper.style.height = interpret(height);
            }
            if (this.options.lineWrapping) {
                clearLineMeasurementCache(this);
            }
            var lineNo$$1 = this.display.viewFrom;
            this.doc.iter(lineNo$$1, this.display.viewTo, function (line) {
                if (line.widgets) {
                    for (var i = 0; i < line.widgets.length; i++) {
                        if (line.widgets[i].noHScroll) {
                            regLineChange(this$1, lineNo$$1, "widget");
                            break
                        }
                    }
                }
                ++lineNo$$1;
            });
            this.curOp.forceUpdate = true;
            signal(this, "refresh", this);
        }),

        operation: function (f) {
            return runInOp(this, f)
        },
        startOperation: function () {
            return startOperation(this)
        },
        endOperation: function () {
            return endOperation(this)
        },

        refresh: methodOp(function () {
            var oldHeight = this.display.cachedTextHeight;
            regChange(this);
            this.curOp.forceUpdate = true;
            clearCaches(this);
            scrollToCoords(this, this.doc.scrollLeft, this.doc.scrollTop);
            updateGutterSpace(this.display);
            if (oldHeight == null || Math.abs(oldHeight - textHeight(this.display)) > .5) {
                estimateLineHeights(this);
            }
            signal(this, "refresh", this);
        }),

        swapDoc: methodOp(function (doc) {
            var old = this.doc;
            old.cm = null;
            // Cancel the current text selection if any (#5821)
            if (this.state.selectingText) {
                this.state.selectingText();
            }
            attachDoc(this, doc);
            clearCaches(this);
            this.display.input.reset();
            scrollToCoords(this, doc.scrollLeft, doc.scrollTop);
            this.curOp.forceScroll = true;
            signalLater(this, "swapDoc", this, old);
            return old
        }),

        phrase: function (phraseText) {
            var phrases = this.options.phrases;
            return phrases && Object.prototype.hasOwnProperty.call(phrases, phraseText) ? phrases[phraseText] : phraseText
        },

        getInputField: function () {
            return this.display.input.getField()
        },
        getWrapperElement: function () {
            return this.display.wrapper
        },
        getScrollerElement: function () {
            return this.display.scroller
        },
        getGutterElement: function () {
            return this.display.gutters
        }
    };
    eventMixin(CodeMirror);

    CodeMirror.registerHelper = function (type, name, value) {
        if (!helpers.hasOwnProperty(type)) {
            helpers[type] = CodeMirror[type] = {_global: []};
        }
        helpers[type][name] = value;
    };
    CodeMirror.registerGlobalHelper = function (type, name, predicate, value) {
        CodeMirror.registerHelper(type, name, value);
        helpers[type]._global.push({pred: predicate, val: value});
    };
}

// Used for horizontal relative motion. Dir is -1 or 1 (left or
// right), unit can be "char", "column" (like char, but doesn't
// cross line boundaries), "word" (across next word), or "group" (to
// the start of next group of word or non-word-non-whitespace
// chars). The visually param controls whether, in right-to-left
// text, direction 1 means to move towards the next index in the
// string, or towards the character to the right of the current
// position. The resulting position will have a hitSide=true
// property if it reached the end of the document.
function findPosH(doc, pos, dir, unit, visually) {
    var oldPos = pos;
    var origDir = dir;
    var lineObj = getLine(doc, pos.line);

    function findNextLine() {
        var l = pos.line + dir;
        if (l < doc.first || l >= doc.first + doc.size) {
            return false
        }
        pos = new Pos(l, pos.ch, pos.sticky);
        return lineObj = getLine(doc, l)
    }

    function moveOnce(boundToLine) {
        var next;
        if (visually) {
            next = moveVisually(doc.cm, lineObj, pos, dir);
        } else {
            next = moveLogically(lineObj, pos, dir);
        }
        if (next == null) {
            if (!boundToLine && findNextLine()) {
                pos = endOfLine(visually, doc.cm, lineObj, pos.line, dir);
            } else {
                return false
            }
        } else {
            pos = next;
        }
        return true
    }

    if (unit == "char") {
        moveOnce();
    } else if (unit == "column") {
        moveOnce(true);
    } else if (unit == "word" || unit == "group") {
        var sawType = null, group = unit == "group";
        var helper = doc.cm && doc.cm.getHelper(pos, "wordChars");
        for (var first = true; ; first = false) {
            if (dir < 0 && !moveOnce(!first)) {
                break
            }
            var cur = lineObj.text.charAt(pos.ch) || "\n";
            var type = isWordChar(cur, helper) ? "w"
                : group && cur == "\n" ? "n"
                    : !group || /\s/.test(cur) ? null
                        : "p";
            if (group && !first && !type) {
                type = "s";
            }
            if (sawType && sawType != type) {
                if (dir < 0) {
                    dir = 1;
                    moveOnce();
                    pos.sticky = "after";
                }
                break
            }

            if (type) {
                sawType = type;
            }
            if (dir > 0 && !moveOnce(!first)) {
                break
            }
        }
    }
    var result = skipAtomic(doc, pos, oldPos, origDir, true);
    if (equalCursorPos(oldPos, result)) {
        result.hitSide = true;
    }
    return result
}

// For relative vertical movement. Dir may be -1 or 1. Unit can be
// "page" or "line". The resulting position will have a hitSide=true
// property if it reached the end of the document.
function findPosV(cm, pos, dir, unit) {
    var doc = cm.doc, x = pos.left, y;
    if (unit == "page") {
        var pageSize = Math.min(cm.display.wrapper.clientHeight, window.innerHeight || document.documentElement.clientHeight);
        var moveAmount = Math.max(pageSize - .5 * textHeight(cm.display), 3);
        y = (dir > 0 ? pos.bottom : pos.top) + dir * moveAmount;

    } else if (unit == "line") {
        y = dir > 0 ? pos.bottom + 3 : pos.top - 3;
    }
    var target;
    for (; ;) {
        target = coordsChar(cm, x, y);
        if (!target.outside) {
            break
        }
        if (dir < 0 ? y <= 0 : y >= doc.height) {
            target.hitSide = true;
            break
        }
        y += dir * 5;
    }
    return target
}

// CONTENTEDITABLE INPUT STYLE

var ContentEditableInput = function (cm) {
    this.cm = cm;
    this.lastAnchorNode = this.lastAnchorOffset = this.lastFocusNode = this.lastFocusOffset = null;
    this.polling = new Delayed();
    this.composing = null;
    this.gracePeriod = false;
    this.readDOMTimeout = null;
};

ContentEditableInput.prototype.init = function (display) {
    var this$1 = this;

    var input = this, cm = input.cm;
    var div = input.div = display.lineDiv;
    disableBrowserMagic(div, cm.options.spellcheck, cm.options.autocorrect, cm.options.autocapitalize);

    on(div, "paste", function (e) {
        if (signalDOMEvent(cm, e) || handlePaste(e, cm)) {
            return
        }
        // IE doesn't fire input events, so we schedule a read for the pasted content in this way
        if (ie_version <= 11) {
            setTimeout(operation(cm, function () {
                return this$1.updateFromDOM();
            }), 20);
        }
    });

    on(div, "compositionstart", function (e) {
        this$1.composing = {data: e.data, done: false};
    });
    on(div, "compositionupdate", function (e) {
        if (!this$1.composing) {
            this$1.composing = {data: e.data, done: false};
        }
    });
    on(div, "compositionend", function (e) {
        if (this$1.composing) {
            if (e.data != this$1.composing.data) {
                this$1.readFromDOMSoon();
            }
            this$1.composing.done = true;
        }
    });

    on(div, "touchstart", function () {
        return input.forceCompositionEnd();
    });

    on(div, "input", function () {
        if (!this$1.composing) {
            this$1.readFromDOMSoon();
        }
    });

    function onCopyCut(e) {
        if (signalDOMEvent(cm, e)) {
            return
        }
        if (cm.somethingSelected()) {
            setLastCopied({lineWise: false, text: cm.getSelections()});
            if (e.type == "cut") {
                cm.replaceSelection("", null, "cut");
            }
        } else if (!cm.options.lineWiseCopyCut) {
            return
        } else {
            var ranges = copyableRanges(cm);
            setLastCopied({lineWise: true, text: ranges.text});
            if (e.type == "cut") {
                cm.operation(function () {
                    cm.setSelections(ranges.ranges, 0, sel_dontScroll);
                    cm.replaceSelection("", null, "cut");
                });
            }
        }
        if (e.clipboardData) {
            e.clipboardData.clearData();
            var content = lastCopied.text.join("\n");
            // iOS exposes the clipboard API, but seems to discard content inserted into it
            e.clipboardData.setData("Text", content);
            if (e.clipboardData.getData("Text") == content) {
                e.preventDefault();
                return
            }
        }
        // Old-fashioned briefly-focus-a-textarea hack
        var kludge = hiddenTextarea(), te = kludge.firstChild;
        cm.display.lineSpace.insertBefore(kludge, cm.display.lineSpace.firstChild);
        te.value = lastCopied.text.join("\n");
        var hadFocus = document.activeElement;
        selectInput(te);
        setTimeout(function () {
            cm.display.lineSpace.removeChild(kludge);
            hadFocus.focus();
            if (hadFocus == div) {
                input.showPrimarySelection();
            }
        }, 50);
    }

    on(div, "copy", onCopyCut);
    on(div, "cut", onCopyCut);
};

ContentEditableInput.prototype.prepareSelection = function () {
    var result = prepareSelection(this.cm, false);
    result.focus = this.cm.state.focused;
    return result
};

ContentEditableInput.prototype.showSelection = function (info, takeFocus) {
    if (!info || !this.cm.display.view.length) {
        return
    }
    if (info.focus || takeFocus) {
        this.showPrimarySelection();
    }
    this.showMultipleSelections(info);
};

ContentEditableInput.prototype.getSelection = function () {
    return this.cm.display.wrapper.ownerDocument.getSelection()
};

ContentEditableInput.prototype.showPrimarySelection = function () {
    var sel = this.getSelection(), cm = this.cm, prim = cm.doc.sel.primary();
    var from = prim.from(), to = prim.to();

    if (cm.display.viewTo == cm.display.viewFrom || from.line >= cm.display.viewTo || to.line < cm.display.viewFrom) {
        sel.removeAllRanges();
        return
    }

    var curAnchor = domToPos(cm, sel.anchorNode, sel.anchorOffset);
    var curFocus = domToPos(cm, sel.focusNode, sel.focusOffset);
    if (curAnchor && !curAnchor.bad && curFocus && !curFocus.bad &&
        cmp(minPos(curAnchor, curFocus), from) == 0 &&
        cmp(maxPos(curAnchor, curFocus), to) == 0) {
        return
    }

    var view = cm.display.view;
    var start = (from.line >= cm.display.viewFrom && posToDOM(cm, from)) ||
        {node: view[0].measure.map[2], offset: 0};
    var end = to.line < cm.display.viewTo && posToDOM(cm, to);
    if (!end) {
        var measure = view[view.length - 1].measure;
        var map$$1 = measure.maps ? measure.maps[measure.maps.length - 1] : measure.map;
        end = {node: map$$1[map$$1.length - 1], offset: map$$1[map$$1.length - 2] - map$$1[map$$1.length - 3]};
    }

    if (!start || !end) {
        sel.removeAllRanges();
        return
    }

    var old = sel.rangeCount && sel.getRangeAt(0), rng;
    try {
        rng = range(start.node, start.offset, end.offset, end.node);
    } catch (e) {
    } // Our model of the DOM might be outdated, in which case the range we try to set can be impossible
    if (rng) {
        if (!gecko && cm.state.focused) {
            sel.collapse(start.node, start.offset);
            if (!rng.collapsed) {
                sel.removeAllRanges();
                sel.addRange(rng);
            }
        } else {
            sel.removeAllRanges();
            sel.addRange(rng);
        }
        if (old && sel.anchorNode == null) {
            sel.addRange(old);
        } else if (gecko) {
            this.startGracePeriod();
        }
    }
    this.rememberSelection();
};

ContentEditableInput.prototype.startGracePeriod = function () {
    var this$1 = this;

    clearTimeout(this.gracePeriod);
    this.gracePeriod = setTimeout(function () {
        this$1.gracePeriod = false;
        if (this$1.selectionChanged()) {
            this$1.cm.operation(function () {
                return this$1.cm.curOp.selectionChanged = true;
            });
        }
    }, 20);
};

ContentEditableInput.prototype.showMultipleSelections = function (info) {
    removeChildrenAndAdd(this.cm.display.cursorDiv, info.cursors);
    removeChildrenAndAdd(this.cm.display.selectionDiv, info.selection);
};

ContentEditableInput.prototype.rememberSelection = function () {
    var sel = this.getSelection();
    this.lastAnchorNode = sel.anchorNode;
    this.lastAnchorOffset = sel.anchorOffset;
    this.lastFocusNode = sel.focusNode;
    this.lastFocusOffset = sel.focusOffset;
};

ContentEditableInput.prototype.selectionInEditor = function () {
    var sel = this.getSelection();
    if (!sel.rangeCount) {
        return false
    }
    var node = sel.getRangeAt(0).commonAncestorContainer;
    return contains(this.div, node)
};

ContentEditableInput.prototype.focus = function () {
    if (this.cm.options.readOnly != "nocursor") {
        if (!this.selectionInEditor()) {
            this.showSelection(this.prepareSelection(), true);
        }
        this.div.focus();
    }
};
ContentEditableInput.prototype.blur = function () {
    this.div.blur();
};
ContentEditableInput.prototype.getField = function () {
    return this.div
};

ContentEditableInput.prototype.supportsTouch = function () {
    return true
};

ContentEditableInput.prototype.receivedFocus = function () {
    var input = this;
    if (this.selectionInEditor()) {
        this.pollSelection();
    } else {
        runInOp(this.cm, function () {
            return input.cm.curOp.selectionChanged = true;
        });
    }

    function poll() {
        if (input.cm.state.focused) {
            input.pollSelection();
            input.polling.set(input.cm.options.pollInterval, poll);
        }
    }

    this.polling.set(this.cm.options.pollInterval, poll);
};

ContentEditableInput.prototype.selectionChanged = function () {
    var sel = this.getSelection();
    return sel.anchorNode != this.lastAnchorNode || sel.anchorOffset != this.lastAnchorOffset ||
        sel.focusNode != this.lastFocusNode || sel.focusOffset != this.lastFocusOffset
};

ContentEditableInput.prototype.pollSelection = function () {
    if (this.readDOMTimeout != null || this.gracePeriod || !this.selectionChanged()) {
        return
    }
    var sel = this.getSelection(), cm = this.cm;
    // On Android Chrome (version 56, at least), backspacing into an
    // uneditable block element will put the cursor in that element,
    // and then, because it's not editable, hide the virtual keyboard.
    // Because Android doesn't allow us to actually detect backspace
    // presses in a sane way, this code checks for when that happens
    // and simulates a backspace press in this case.
    if (android && chrome && this.cm.display.gutterSpecs.length && isInGutter(sel.anchorNode)) {
        this.cm.triggerOnKeyDown({type: "keydown", keyCode: 8, preventDefault: Math.abs});
        this.blur();
        this.focus();
        return
    }
    if (this.composing) {
        return
    }
    this.rememberSelection();
    var anchor = domToPos(cm, sel.anchorNode, sel.anchorOffset);
    var head = domToPos(cm, sel.focusNode, sel.focusOffset);
    if (anchor && head) {
        runInOp(cm, function () {
            setSelection(cm.doc, simpleSelection(anchor, head), sel_dontScroll);
            if (anchor.bad || head.bad) {
                cm.curOp.selectionChanged = true;
            }
        });
    }
};

ContentEditableInput.prototype.pollContent = function () {
    if (this.readDOMTimeout != null) {
        clearTimeout(this.readDOMTimeout);
        this.readDOMTimeout = null;
    }

    var cm = this.cm, display = cm.display, sel = cm.doc.sel.primary();
    var from = sel.from(), to = sel.to();
    if (from.ch == 0 && from.line > cm.firstLine()) {
        from = Pos(from.line - 1, getLine(cm.doc, from.line - 1).length);
    }
    if (to.ch == getLine(cm.doc, to.line).text.length && to.line < cm.lastLine()) {
        to = Pos(to.line + 1, 0);
    }
    if (from.line < display.viewFrom || to.line > display.viewTo - 1) {
        return false
    }

    var fromIndex, fromLine, fromNode;
    if (from.line == display.viewFrom || (fromIndex = findViewIndex(cm, from.line)) == 0) {
        fromLine = lineNo(display.view[0].line);
        fromNode = display.view[0].node;
    } else {
        fromLine = lineNo(display.view[fromIndex].line);
        fromNode = display.view[fromIndex - 1].node.nextSibling;
    }
    var toIndex = findViewIndex(cm, to.line);
    var toLine, toNode;
    if (toIndex == display.view.length - 1) {
        toLine = display.viewTo - 1;
        toNode = display.lineDiv.lastChild;
    } else {
        toLine = lineNo(display.view[toIndex + 1].line) - 1;
        toNode = display.view[toIndex + 1].node.previousSibling;
    }

    if (!fromNode) {
        return false
    }
    var newText = cm.doc.splitLines(domTextBetween(cm, fromNode, toNode, fromLine, toLine));
    var oldText = getBetween(cm.doc, Pos(fromLine, 0), Pos(toLine, getLine(cm.doc, toLine).text.length));
    while (newText.length > 1 && oldText.length > 1) {
        if (lst(newText) == lst(oldText)) {
            newText.pop();
            oldText.pop();
            toLine--;
        } else if (newText[0] == oldText[0]) {
            newText.shift();
            oldText.shift();
            fromLine++;
        } else {
            break
        }
    }

    var cutFront = 0, cutEnd = 0;
    var newTop = newText[0], oldTop = oldText[0], maxCutFront = Math.min(newTop.length, oldTop.length);
    while (cutFront < maxCutFront && newTop.charCodeAt(cutFront) == oldTop.charCodeAt(cutFront)) {
        ++cutFront;
    }
    var newBot = lst(newText), oldBot = lst(oldText);
    var maxCutEnd = Math.min(newBot.length - (newText.length == 1 ? cutFront : 0),
        oldBot.length - (oldText.length == 1 ? cutFront : 0));
    while (cutEnd < maxCutEnd &&
    newBot.charCodeAt(newBot.length - cutEnd - 1) == oldBot.charCodeAt(oldBot.length - cutEnd - 1)) {
        ++cutEnd;
    }
    // Try to move start of change to start of selection if ambiguous
    if (newText.length == 1 && oldText.length == 1 && fromLine == from.line) {
        while (cutFront && cutFront > from.ch &&
        newBot.charCodeAt(newBot.length - cutEnd - 1) == oldBot.charCodeAt(oldBot.length - cutEnd - 1)) {
            cutFront--;
            cutEnd++;
        }
    }

    newText[newText.length - 1] = newBot.slice(0, newBot.length - cutEnd).replace(/^\u200b+/, "");
    newText[0] = newText[0].slice(cutFront).replace(/\u200b+$/, "");

    var chFrom = Pos(fromLine, cutFront);
    var chTo = Pos(toLine, oldText.length ? lst(oldText).length - cutEnd : 0);
    if (newText.length > 1 || newText[0] || cmp(chFrom, chTo)) {
        replaceRange(cm.doc, newText, chFrom, chTo, "+input");
        return true
    }
};

ContentEditableInput.prototype.ensurePolled = function () {
    this.forceCompositionEnd();
};
ContentEditableInput.prototype.reset = function () {
    this.forceCompositionEnd();
};
ContentEditableInput.prototype.forceCompositionEnd = function () {
    if (!this.composing) {
        return
    }
    clearTimeout(this.readDOMTimeout);
    this.composing = null;
    this.updateFromDOM();
    this.div.blur();
    this.div.focus();
};
ContentEditableInput.prototype.readFromDOMSoon = function () {
    var this$1 = this;

    if (this.readDOMTimeout != null) {
        return
    }
    this.readDOMTimeout = setTimeout(function () {
        this$1.readDOMTimeout = null;
        if (this$1.composing) {
            if (this$1.composing.done) {
                this$1.composing = null;
            } else {
                return
            }
        }
        this$1.updateFromDOM();
    }, 80);
};

ContentEditableInput.prototype.updateFromDOM = function () {
    var this$1 = this;

    if (this.cm.isReadOnly() || !this.pollContent()) {
        runInOp(this.cm, function () {
            return regChange(this$1.cm);
        });
    }
};

ContentEditableInput.prototype.setUneditable = function (node) {
    node.contentEditable = "false";
};

ContentEditableInput.prototype.onKeyPress = function (e) {
    if (e.charCode == 0 || this.composing) {
        return
    }
    e.preventDefault();
    if (!this.cm.isReadOnly()) {
        operation(this.cm, applyTextInput)(this.cm, String.fromCharCode(e.charCode == null ? e.keyCode : e.charCode), 0);
    }
};

ContentEditableInput.prototype.readOnlyChanged = function (val) {
    this.div.contentEditable = String(val != "nocursor");
};

ContentEditableInput.prototype.onContextMenu = function () {
};
ContentEditableInput.prototype.resetPosition = function () {
};

ContentEditableInput.prototype.needsContentAttribute = true;

function posToDOM(cm, pos) {
    var view = findViewForLine(cm, pos.line);
    if (!view || view.hidden) {
        return null
    }
    var line = getLine(cm.doc, pos.line);
    var info = mapFromLineView(view, line, pos.line);

    var order = getOrder(line, cm.doc.direction), side = "left";
    if (order) {
        var partPos = getBidiPartAt(order, pos.ch);
        side = partPos % 2 ? "right" : "left";
    }
    var result = nodeAndOffsetInLineMap(info.map, pos.ch, side);
    result.offset = result.collapse == "right" ? result.end : result.start;
    return result
}

function isInGutter(node) {
    for (var scan = node; scan; scan = scan.parentNode) {
        if (/CodeMirror-gutter-wrapper/.test(scan.className)) {
            return true
        }
    }
    return false
}

function badPos(pos, bad) {
    if (bad) {
        pos.bad = true;
    }
    return pos
}

function domTextBetween(cm, from, to, fromLine, toLine) {
    var text = "", closing = false, lineSep = cm.doc.lineSeparator(), extraLinebreak = false;

    function recognizeMarker(id) {
        return function (marker) {
            return marker.id == id;
        }
    }

    function close() {
        if (closing) {
            text += lineSep;
            if (extraLinebreak) {
                text += lineSep;
            }
            closing = extraLinebreak = false;
        }
    }

    function addText(str) {
        if (str) {
            close();
            text += str;
        }
    }

    function walk(node) {
        if (node.nodeType == 1) {
            var cmText = node.getAttribute("cm-text");
            if (cmText) {
                addText(cmText);
                return
            }
            var markerID = node.getAttribute("cm-marker"), range$$1;
            if (markerID) {
                var found = cm.findMarks(Pos(fromLine, 0), Pos(toLine + 1, 0), recognizeMarker(+markerID));
                if (found.length && (range$$1 = found[0].find(0))) {
                    addText(getBetween(cm.doc, range$$1.from, range$$1.to).join(lineSep));
                }
                return
            }
            if (node.getAttribute("contenteditable") == "false") {
                return
            }
            var isBlock = /^(pre|div|p|li|table|br)$/i.test(node.nodeName);
            if (!/^br$/i.test(node.nodeName) && node.textContent.length == 0) {
                return
            }

            if (isBlock) {
                close();
            }
            for (var i = 0; i < node.childNodes.length; i++) {
                walk(node.childNodes[i]);
            }

            if (/^(pre|p)$/i.test(node.nodeName)) {
                extraLinebreak = true;
            }
            if (isBlock) {
                closing = true;
            }
        } else if (node.nodeType == 3) {
            addText(node.nodeValue.replace(/\u200b/g, "").replace(/\u00a0/g, " "));
        }
    }

    for (; ;) {
        walk(from);
        if (from == to) {
            break
        }
        from = from.nextSibling;
        extraLinebreak = false;
    }
    return text
}

function domToPos(cm, node, offset) {
    var lineNode;
    if (node == cm.display.lineDiv) {
        lineNode = cm.display.lineDiv.childNodes[offset];
        if (!lineNode) {
            return badPos(cm.clipPos(Pos(cm.display.viewTo - 1)), true)
        }
        node = null;
        offset = 0;
    } else {
        for (lineNode = node; ; lineNode = lineNode.parentNode) {
            if (!lineNode || lineNode == cm.display.lineDiv) {
                return null
            }
            if (lineNode.parentNode && lineNode.parentNode == cm.display.lineDiv) {
                break
            }
        }
    }
    for (var i = 0; i < cm.display.view.length; i++) {
        var lineView = cm.display.view[i];
        if (lineView.node == lineNode) {
            return locateNodeInLineView(lineView, node, offset)
        }
    }
}

function locateNodeInLineView(lineView, node, offset) {
    var wrapper = lineView.text.firstChild, bad = false;
    if (!node || !contains(wrapper, node)) {
        return badPos(Pos(lineNo(lineView.line), 0), true)
    }
    if (node == wrapper) {
        bad = true;
        node = wrapper.childNodes[offset];
        offset = 0;
        if (!node) {
            var line = lineView.rest ? lst(lineView.rest) : lineView.line;
            return badPos(Pos(lineNo(line), line.text.length), bad)
        }
    }

    var textNode = node.nodeType == 3 ? node : null, topNode = node;
    if (!textNode && node.childNodes.length == 1 && node.firstChild.nodeType == 3) {
        textNode = node.firstChild;
        if (offset) {
            offset = textNode.nodeValue.length;
        }
    }
    while (topNode.parentNode != wrapper) {
        topNode = topNode.parentNode;
    }
    var measure = lineView.measure, maps = measure.maps;

    function find(textNode, topNode, offset) {
        for (var i = -1; i < (maps ? maps.length : 0); i++) {
            var map$$1 = i < 0 ? measure.map : maps[i];
            for (var j = 0; j < map$$1.length; j += 3) {
                var curNode = map$$1[j + 2];
                if (curNode == textNode || curNode == topNode) {
                    var line = lineNo(i < 0 ? lineView.line : lineView.rest[i]);
                    var ch = map$$1[j] + offset;
                    if (offset < 0 || curNode != textNode) {
                        ch = map$$1[j + (offset ? 1 : 0)];
                    }
                    return Pos(line, ch)
                }
            }
        }
    }

    var found = find(textNode, topNode, offset);
    if (found) {
        return badPos(found, bad)
    }

    // FIXME this is all really shaky. might handle the few cases it needs to handle, but likely to cause problems
    for (var after = topNode.nextSibling, dist = textNode ? textNode.nodeValue.length - offset : 0; after; after = after.nextSibling) {
        found = find(after, after.firstChild, 0);
        if (found) {
            return badPos(Pos(found.line, found.ch - dist), bad)
        } else {
            dist += after.textContent.length;
        }
    }
    for (var before = topNode.previousSibling, dist$1 = offset; before; before = before.previousSibling) {
        found = find(before, before.firstChild, -1);
        if (found) {
            return badPos(Pos(found.line, found.ch + dist$1), bad)
        } else {
            dist$1 += before.textContent.length;
        }
    }
}

// TEXTAREA INPUT STYLE

var TextareaInput = function (cm) {
    this.cm = cm;
    // See input.poll and input.reset
    this.prevInput = "";

    // Flag that indicates whether we expect input to appear real soon
    // now (after some event like 'keypress' or 'input') and are
    // polling intensively.
    this.pollingFast = false;
    // Self-resetting timeout for the poller
    this.polling = new Delayed();
    // Used to work around IE issue with selection being forgotten when focus moves away from textarea
    this.hasSelection = false;
    this.composing = null;
};

TextareaInput.prototype.init = function (display) {
    var this$1 = this;

    var input = this, cm = this.cm;
    this.createField(display);
    var te = this.textarea;

    display.wrapper.insertBefore(this.wrapper, display.wrapper.firstChild);

    // Needed to hide big blue blinking cursor on Mobile Safari (doesn't seem to work in iOS 8 anymore)
    if (ios) {
        te.style.width = "0px";
    }

    on(te, "input", function () {
        if (ie && ie_version >= 9 && this$1.hasSelection) {
            this$1.hasSelection = null;
        }
        input.poll();
    });

    on(te, "paste", function (e) {
        if (signalDOMEvent(cm, e) || handlePaste(e, cm)) {
            return
        }

        cm.state.pasteIncoming = +new Date;
        input.fastPoll();
    });

    function prepareCopyCut(e) {
        if (signalDOMEvent(cm, e)) {
            return
        }
        if (cm.somethingSelected()) {
            setLastCopied({lineWise: false, text: cm.getSelections()});
        } else if (!cm.options.lineWiseCopyCut) {
            return
        } else {
            var ranges = copyableRanges(cm);
            setLastCopied({lineWise: true, text: ranges.text});
            if (e.type == "cut") {
                cm.setSelections(ranges.ranges, null, sel_dontScroll);
            } else {
                input.prevInput = "";
                te.value = ranges.text.join("\n");
                selectInput(te);
            }
        }
        if (e.type == "cut") {
            cm.state.cutIncoming = +new Date;
        }
    }

    on(te, "cut", prepareCopyCut);
    on(te, "copy", prepareCopyCut);

    on(display.scroller, "paste", function (e) {
        if (eventInWidget(display, e) || signalDOMEvent(cm, e)) {
            return
        }
        if (!te.dispatchEvent) {
            cm.state.pasteIncoming = +new Date;
            input.focus();
            return
        }

        // Pass the `paste` event to the textarea so it's handled by its event listener.
        var event = new Event("paste");
        event.clipboardData = e.clipboardData;
        te.dispatchEvent(event);
    });

    // Prevent normal selection in the src (we handle our own)
    on(display.lineSpace, "selectstart", function (e) {
        if (!eventInWidget(display, e)) {
            e_preventDefault(e);
        }
    });

    on(te, "compositionstart", function () {
        var start = cm.getCursor("from");
        if (input.composing) {
            input.composing.range.clear();
        }
        input.composing = {
            start: start,
            range: cm.markText(start, cm.getCursor("to"), {className: "CodeMirror-composing"})
        };
    });
    on(te, "compositionend", function () {
        if (input.composing) {
            input.poll();
            input.composing.range.clear();
            input.composing = null;
        }
    });
};

TextareaInput.prototype.createField = function (_display) {
    // Wraps and hides input textarea
    this.wrapper = hiddenTextarea();
    // The semihidden textarea that is focused when the src is
    // focused, and receives input.
    this.textarea = this.wrapper.firstChild;
};

TextareaInput.prototype.prepareSelection = function () {
    // Redraw the selection and/or cursor
    var cm = this.cm, display = cm.display, doc = cm.doc;
    var result = prepareSelection(cm);

    // Move the hidden textarea near the cursor to prevent scrolling artifacts
    if (cm.options.moveInputWithCursor) {
        var headPos = cursorCoords(cm, doc.sel.primary().head, "div");
        var wrapOff = display.wrapper.getBoundingClientRect(), lineOff = display.lineDiv.getBoundingClientRect();
        result.teTop = Math.max(0, Math.min(display.wrapper.clientHeight - 10,
            headPos.top + lineOff.top - wrapOff.top));
        result.teLeft = Math.max(0, Math.min(display.wrapper.clientWidth - 10,
            headPos.left + lineOff.left - wrapOff.left));
    }

    return result
};

TextareaInput.prototype.showSelection = function (drawn) {
    var cm = this.cm, display = cm.display;
    removeChildrenAndAdd(display.cursorDiv, drawn.cursors);
    removeChildrenAndAdd(display.selectionDiv, drawn.selection);
    if (drawn.teTop != null) {
        this.wrapper.style.top = drawn.teTop + "px";
        this.wrapper.style.left = drawn.teLeft + "px";
    }
};

// Reset the input to correspond to the selection (or to be empty,
// when not typing and nothing is selected)
TextareaInput.prototype.reset = function (typing) {
    if (this.contextMenuPending || this.composing) {
        return
    }
    var cm = this.cm;
    if (cm.somethingSelected()) {
        this.prevInput = "";
        var content = cm.getSelection();
        this.textarea.value = content;
        if (cm.state.focused) {
            selectInput(this.textarea);
        }
        if (ie && ie_version >= 9) {
            this.hasSelection = content;
        }
    } else if (!typing) {
        this.prevInput = this.textarea.value = "";
        if (ie && ie_version >= 9) {
            this.hasSelection = null;
        }
    }
};

TextareaInput.prototype.getField = function () {
    return this.textarea
};

TextareaInput.prototype.supportsTouch = function () {
    return false
};

TextareaInput.prototype.focus = function () {
    if (this.cm.options.readOnly != "nocursor" && (!mobile || activeElt() != this.textarea)) {
        try {
            this.textarea.focus();
        } catch (e) {
        } // IE8 will throw if the textarea is display: none or not in DOM
    }
};

TextareaInput.prototype.blur = function () {
    this.textarea.blur();
};

TextareaInput.prototype.resetPosition = function () {
    this.wrapper.style.top = this.wrapper.style.left = 0;
};

TextareaInput.prototype.receivedFocus = function () {
    this.slowPoll();
};

// Poll for input changes, using the normal rate of polling. This
// runs as long as the src is focused.
TextareaInput.prototype.slowPoll = function () {
    var this$1 = this;

    if (this.pollingFast) {
        return
    }
    this.polling.set(this.cm.options.pollInterval, function () {
        this$1.poll();
        if (this$1.cm.state.focused) {
            this$1.slowPoll();
        }
    });
};

// When an event has just come in that is likely to add or change
// something in the input textarea, we poll faster, to ensure that
// the change appears on the screen quickly.
TextareaInput.prototype.fastPoll = function () {
    var missed = false, input = this;
    input.pollingFast = true;

    function p() {
        var changed = input.poll();
        if (!changed && !missed) {
            missed = true;
            input.polling.set(60, p);
        } else {
            input.pollingFast = false;
            input.slowPoll();
        }
    }

    input.polling.set(20, p);
};

// Read input from the textarea, and update the document to match.
// When something is selected, it is present in the textarea, and
// selected (unless it is huge, in which case a placeholder is
// used). When nothing is selected, the cursor sits after previously
// seen text (can be empty), which is stored in prevInput (we must
// not reset the textarea when typing, because that breaks IME).
TextareaInput.prototype.poll = function () {
    var this$1 = this;

    var cm = this.cm, input = this.textarea, prevInput = this.prevInput;
    // Since this is called a *lot*, try to bail out as cheaply as
    // possible when it is clear that nothing happened. hasSelection
    // will be the case when there is a lot of text in the textarea,
    // in which case reading its value would be expensive.
    if (this.contextMenuPending || !cm.state.focused ||
        (hasSelection(input) && !prevInput && !this.composing) ||
        cm.isReadOnly() || cm.options.disableInput || cm.state.keySeq) {
        return false
    }

    var text = input.value;
    // If nothing changed, bail.
    if (text == prevInput && !cm.somethingSelected()) {
        return false
    }
    // Work around nonsensical selection resetting in IE9/10, and
    // inexplicable appearance of private area unicode characters on
    // some key combos in Mac (#2689).
    if (ie && ie_version >= 9 && this.hasSelection === text ||
        mac && /[\uf700-\uf7ff]/.test(text)) {
        cm.display.input.reset();
        return false
    }

    if (cm.doc.sel == cm.display.selForContextMenu) {
        var first = text.charCodeAt(0);
        if (first == 0x200b && !prevInput) {
            prevInput = "\u200b";
        }
        if (first == 0x21da) {
            this.reset();
            return this.cm.execCommand("undo")
        }
    }
    // Find the part of the input that is actually new
    var same = 0, l = Math.min(prevInput.length, text.length);
    while (same < l && prevInput.charCodeAt(same) == text.charCodeAt(same)) {
        ++same;
    }

    runInOp(cm, function () {
        applyTextInput(cm, text.slice(same), prevInput.length - same,
            null, this$1.composing ? "*compose" : null);

        // Don't leave long text in the textarea, since it makes further polling slow
        if (text.length > 1000 || text.indexOf("\n") > -1) {
            input.value = this$1.prevInput = "";
        } else {
            this$1.prevInput = text;
        }

        if (this$1.composing) {
            this$1.composing.range.clear();
            this$1.composing.range = cm.markText(this$1.composing.start, cm.getCursor("to"),
                {className: "CodeMirror-composing"});
        }
    });
    return true
};

TextareaInput.prototype.ensurePolled = function () {
    if (this.pollingFast && this.poll()) {
        this.pollingFast = false;
    }
};

TextareaInput.prototype.onKeyPress = function () {
    if (ie && ie_version >= 9) {
        this.hasSelection = null;
    }
    this.fastPoll();
};

TextareaInput.prototype.onContextMenu = function (e) {
    var input = this, cm = input.cm, display = cm.display, te = input.textarea;
    if (input.contextMenuPending) {
        input.contextMenuPending();
    }
    var pos = posFromMouse(cm, e), scrollPos = display.scroller.scrollTop;
    if (!pos || presto) {
        return
    } // Opera is difficult.

    // Reset the current text selection only if the click is done outside of the selection
    // and 'resetSelectionOnContextMenu' option is true.
    var reset = cm.options.resetSelectionOnContextMenu;
    if (reset && cm.doc.sel.contains(pos) == -1) {
        operation(cm, setSelection)(cm.doc, simpleSelection(pos), sel_dontScroll);
    }

    var oldCSS = te.style.cssText, oldWrapperCSS = input.wrapper.style.cssText;
    var wrapperBox = input.wrapper.offsetParent.getBoundingClientRect();
    input.wrapper.style.cssText = "position: static";
    te.style.cssText = "position: absolute; width: 30px; height: 30px;\n      top: " + (e.clientY - wrapperBox.top - 5) + "px; left: " + (e.clientX - wrapperBox.left - 5) + "px;\n      z-index: 1000; background: " + (ie ? "rgba(255, 255, 255, .05)" : "transparent") + ";\n      outline: none; border-width: 0; outline: none; overflow: hidden; opacity: .05; filter: alpha(opacity=5);";
    var oldScrollY;
    if (webkit) {
        oldScrollY = window.scrollY;
    } // Work around Chrome issue (#2712)
    display.input.focus();
    if (webkit) {
        window.scrollTo(null, oldScrollY);
    }
    display.input.reset();
    // Adds "Select all" to context menu in FF
    if (!cm.somethingSelected()) {
        te.value = input.prevInput = " ";
    }
    input.contextMenuPending = rehide;
    display.selForContextMenu = cm.doc.sel;
    clearTimeout(display.detectingSelectAll);

    // Select-all will be greyed out if there's nothing to select, so
    // this adds a zero-width space so that we can later check whether
    // it got selected.
    function prepareSelectAllHack() {
        if (te.selectionStart != null) {
            var selected = cm.somethingSelected();
            var extval = "\u200b" + (selected ? te.value : "");
            te.value = "\u21da"; // Used to catch context-menu undo
            te.value = extval;
            input.prevInput = selected ? "" : "\u200b";
            te.selectionStart = 1;
            te.selectionEnd = extval.length;
            // Re-set this, in case some other handler touched the
            // selection in the meantime.
            display.selForContextMenu = cm.doc.sel;
        }
    }

    function rehide() {
        if (input.contextMenuPending != rehide) {
            return
        }
        input.contextMenuPending = false;
        input.wrapper.style.cssText = oldWrapperCSS;
        te.style.cssText = oldCSS;
        if (ie && ie_version < 9) {
            display.scrollbars.setScrollTop(display.scroller.scrollTop = scrollPos);
        }

        // Try to detect the user choosing select-all
        if (te.selectionStart != null) {
            if (!ie || (ie && ie_version < 9)) {
                prepareSelectAllHack();
            }
            var i = 0, poll = function () {
                if (display.selForContextMenu == cm.doc.sel && te.selectionStart == 0 &&
                    te.selectionEnd > 0 && input.prevInput == "\u200b") {
                    operation(cm, selectAll)(cm);
                } else if (i++ < 10) {
                    display.detectingSelectAll = setTimeout(poll, 500);
                } else {
                    display.selForContextMenu = null;
                    display.input.reset();
                }
            };
            display.detectingSelectAll = setTimeout(poll, 200);
        }
    }

    if (ie && ie_version >= 9) {
        prepareSelectAllHack();
    }
    if (captureRightClick) {
        e_stop(e);
        var mouseup = function () {
            off(window, "mouseup", mouseup);
            setTimeout(rehide, 20);
        };
        on(window, "mouseup", mouseup);
    } else {
        setTimeout(rehide, 50);
    }
};

TextareaInput.prototype.readOnlyChanged = function (val) {
    if (!val) {
        this.reset();
    }
    this.textarea.disabled = val == "nocursor";
};

TextareaInput.prototype.setUneditable = function () {
};

TextareaInput.prototype.needsContentAttribute = false;

function fromTextArea(textarea, options) {
    options = options ? copyObj(options) : {};
    options.value = textarea.value;
    if (!options.tabindex && textarea.tabIndex) {
        options.tabindex = textarea.tabIndex;
    }
    if (!options.placeholder && textarea.placeholder) {
        options.placeholder = textarea.placeholder;
    }
    // Set autofocus to true if this textarea is focused, or if it has
    // autofocus and no other element is focused.
    if (options.autofocus == null) {
        var hasFocus = activeElt();
        options.autofocus = hasFocus == textarea ||
            textarea.getAttribute("autofocus") != null && hasFocus == document.body;
    }

    function save() {
        textarea.value = cm.getValue();
    }

    var realSubmit;
    if (textarea.form) {
        on(textarea.form, "submit", save);
        // Deplorable hack to make the submit method do the right thing.
        if (!options.leaveSubmitMethodAlone) {
            var form = textarea.form;
            realSubmit = form.submit;
            try {
                var wrappedSubmit = form.submit = function () {
                    save();
                    form.submit = realSubmit;
                    form.submit();
                    form.submit = wrappedSubmit;
                };
            } catch (e) {
            }
        }
    }

    options.finishInit = function (cm) {
        cm.save = save;
        cm.getTextArea = function () {
            return textarea;
        };
        cm.toTextArea = function () {
            cm.toTextArea = isNaN; // Prevent this from being ran twice
            save();
            textarea.parentNode.removeChild(cm.getWrapperElement());
            textarea.style.display = "";
            if (textarea.form) {
                off(textarea.form, "submit", save);
                if (!options.leaveSubmitMethodAlone && typeof textarea.form.submit == "function") {
                    textarea.form.submit = realSubmit;
                }
            }
        };
    };

    textarea.style.display = "none";
    var cm = CodeMirror(function (node) {
            return textarea.parentNode.insertBefore(node, textarea.nextSibling);
        },
        options);
    return cm
}

function addLegacyProps(CodeMirror) {
    CodeMirror.off = off;
    CodeMirror.on = on;
    CodeMirror.wheelEventPixels = wheelEventPixels;
    CodeMirror.Doc = Doc;
    CodeMirror.splitLines = splitLinesAuto;
    CodeMirror.countColumn = countColumn;
    CodeMirror.findColumn = findColumn;
    CodeMirror.isWordChar = isWordCharBasic;
    CodeMirror.Pass = Pass;
    CodeMirror.signal = signal;
    CodeMirror.Line = Line;
    CodeMirror.changeEnd = changeEnd;
    CodeMirror.scrollbarModel = scrollbarModel;
    CodeMirror.Pos = Pos;
    CodeMirror.cmpPos = cmp;
    CodeMirror.modes = modes;
    CodeMirror.mimeModes = mimeModes;
    CodeMirror.resolveMode = resolveMode;
    CodeMirror.getMode = getMode;
    CodeMirror.modeExtensions = modeExtensions;
    CodeMirror.extendMode = extendMode;
    CodeMirror.copyState = copyState;
    CodeMirror.startState = startState;
    CodeMirror.innerMode = innerMode;
    CodeMirror.commands = commands;
    CodeMirror.keyMap = keyMap;
    CodeMirror.keyName = keyName;
    CodeMirror.isModifierKey = isModifierKey;
    CodeMirror.lookupKey = lookupKey;
    CodeMirror.normalizeKeyMap = normalizeKeyMap;
    CodeMirror.StringStream = StringStream;
    CodeMirror.SharedTextMarker = SharedTextMarker;
    CodeMirror.TextMarker = TextMarker;
    CodeMirror.LineWidget = LineWidget;
    CodeMirror.e_preventDefault = e_preventDefault;
    CodeMirror.e_stopPropagation = e_stopPropagation;
    CodeMirror.e_stop = e_stop;
    CodeMirror.addClass = addClass;
    CodeMirror.contains = contains;
    CodeMirror.rmClass = rmClass;
    // CodeMirror.keyNames = keyNames;
}

// EDITOR CONSTRUCTOR

defineOptions(CodeMirror);

addEditorMethods(CodeMirror);

// Set up methods on CodeMirror's prototype to redirect to the src's document.
var dontDelegate = "iter insert remove copy getEditor constructor".split(" ");
for (var prop in Doc.prototype) {
    if (Doc.prototype.hasOwnProperty(prop) && indexOf(dontDelegate, prop) < 0) {
        CodeMirror.prototype[prop] = (function (method) {
            return function () {
                return method.apply(this.doc, arguments)
            }
        })(Doc.prototype[prop]);
    }
}

eventMixin(Doc);
CodeMirror.inputStyles = {"textarea": TextareaInput, "contenteditable": ContentEditableInput};

// Extra arguments are stored as the mode's dependencies, which is
// used by (legacy) mechanisms like loadmode.js to automatically
// load a mode. (Preferred mechanism is the require/define calls.)
CodeMirror.defineMode = function (name/*, mode, …*/) {
    if (!CodeMirror.defaults.mode && name != "null") {
        CodeMirror.defaults.mode = name;
    }
    defineMode.apply(this, arguments);
};

CodeMirror.defineMIME = defineMIME;

// Minimal default mode.
CodeMirror.defineMode("null", function () {
    return ({
        token: function (stream) {
            return stream.skipToEnd();
        }
    });
});
CodeMirror.defineMIME("text/plain", "null");

// EXTENSIONS

CodeMirror.defineExtension = function (name, func) {
    CodeMirror.prototype[name] = func;
};
CodeMirror.defineDocExtension = function (name, func) {
    Doc.prototype[name] = func;
};

CodeMirror.fromTextArea = fromTextArea;

addLegacyProps(CodeMirror);


CodeMirror.version = "5.49.2"
window.CodeMirror = CodeMirror;
export default CodeMirror
